High Etendue Finite Conjugate Zoom Lens Assembly with Five Doublets Two Movable Lens Groups

[0001] This application is a Continuation of U.S. patent application Ser. No. 16/558,296, filed Sep. 2, 2019; which is a Continuation of U.S. patent application Ser. No. 15/881,681, filed Jan. 26, 2018, now U.S. Pat. No. 10,401,598; which claims the benefit of priority to U.S. provisional patent applications Ser. Nos. 62/451,060, filed Jan. 26, 2017; and 62/451,622, filed Jan. 27, 2017.

[0002] This application is also related to U.S. Pat. Nos. 10,670,842; 10,678,032; 10,670,843; 10,670,844; 10,401,598; and 10,914,928; and to U.S. patent application Ser. No. 16/889,728; Ser. No. 16/895,332; Ser. No. 16/889,739; Ser. No. 16/889,800; Ser. No. 16/558,296; and Ser. No. 16/826,166.

[0003] Each of these priority and related patents and patent applications is incorporated by reference.

[0004] The invention relates generally to a lens attachment for an optical zoom lens assembly for use in combination with a camera or eyepiece, for the purpose of viewing and inspecting objects. More specifically the invention relates to a lens attachment for an optical assembly or a lens assembly having the characteristics of having high optical etendue preserving characteristics, broad wavelength correction, or a large zoom range, or combinations thereof.

[0005] The history of long working distance finite conjugate lenses with a large zoom range goes back many decades. Bausch and Lomb used a zoom module in their Stereo Zoom 4 through 7 models, which started being produced in 1959. The most commonly produced scope had a 0.7×-3× magnification range, for a ratio of highest magnification (e.g., 3×) to lowest magnification (e.g., 0.7×), of 3/0.7, or approximately 4.3, which may be written as 4.3:1. FIG. 1 shows an eyepiece pod for a conventional Bausch and Lomb StereoZoom4 with 0.7-3× magnification range. FIG. 2 shows a full stereo microscope stand for a conventional Bausch and Lomb StereoZoom4.

[0006] Even at this time the idea of modularity, defined as a pod, was introduced to allow the stereo microscope head to be used on multiple stands and stages. This product was targeted to work with eyepiece magnifiers, which define the limited field of view required, and the limited amount of NA required to achieve vision limited resolution of around 2 arc-min per optical line pairs.

[0007] Technological innovations over time, particularly in the 1980s, eventually progressed along two product development paths, which continue to be in production through the present. One path has involved continued use within stereomicroscopes. An example of a conventional Jeweler's StereoZoom microscope that is still in use today is provided at FIG. 3. The stereo microscope shown in FIG. 3 has a ratio of highest to lowest magnification of 6.5:1, often using a zoom cell with approximately 0.7-4.5× magnification range. An optical assembly in accordance with FIG. 3 can be used with varying eyepiece magnifiers and Barlow lenses to adjust the visual magnification. Another path has involved use of a very similar zoom cell with 6.5:1 ratio of highest to lowest magnification in a monocular arrangement in a video system. These systems functioned to image objects or scenes onto a sensor of up to approximately 11 mm on the diagonal, commonly referred to as a ⅔ inch format camera. This field of view (FOV), along with the approximately maximum rear numerical aperture (NA) of 0.0388, has remained approximately consistent with the original stereo microscope designs. It is recognized herein by the present inventor that these cameras, if utilized to their fullest extent or otherwise optimized for maximum performance quality or efficiency, may in principle achieve a maximum etendue of 0.45 mm²sr (square millimeters steradians) with less than 10% vignetting.

[0008] FIGS. 4A-4C schematically illustrate an example of an optical assembly that may achieve an approximate etendue of 0.45 mm²sr with less than 10% vignetting. Three arrangements are illustrated schematically in FIGS. 4A-4C, including a low magnification arrangement at FIG. 4A, a mid-level magnification arrangement at FIG. 4B, and a high magnification arrangement at FIG. 4C. The optical arrangements shown in FIGS. 4A-4C each include, from object end to image end of the lens assembly, a first static pair of doublets G10, G20, a first movable doublet G30, a second movable doublet G50, and a second static pair of doublets G60, G70. The positions of the movable doublets G30, G50 relative to each of the static doublets G10, G20, G60, G70 is adjustable for selecting a magnification within a range between a lowest and highest magnification of the optical assembly of FIGS. 4A-4C.

[0009] The possibility is recognized herein by the present inventor that, with a notable loss of relative illumination and/or increased aberration, a larger sensor, e.g., having a 16 mm diagonal, or one inch (1″) format, may be combined with the optical assembly of FIGS. 4A-4C such that an approximately same optical assembly as that used in a monocular video system may provide images to a one inch format sensor field in a camera that can operate in an etendue range above 0.45 mm²sr up to approximately 0.95 mm²sr. Such a camera would likely exhibit, however, all else being equal, significantly less than optimal viewing performance or reduced illumination at the outer portions of the field, or both. In the instance of vignetting or loss of illumination at the full diagonal field, a reduction in the angular light cone would mathematically reduce the highest achievable etendue of the optical assembly of FIGS. 4A-4C to less than the 0.95 mm²sr.

[0010] It is desired to have a camera that includes an optical assembly that is configured to exhibit a reduction in loss of optical quality with less than 10% vignetting in an etendue range above 0.95 mm²sr. It is further desired to have such a camera and optical assembly that are configured for operation in the approximately 0.95-4.65 mm²sr etendue range, and particularly such a camera and optical assembly that also exhibits enhanced performance, such as may be demonstrated by a reduction in loss of optical quality with less than 10% vignetting.

[0045] Table 1 includes an example optical prescription for an example afocal zoom optical assembly that is configured in accordance with certain embodiments and is schematically illustrated at FIG. 5.

[0046] Table 2 includes an example optical prescription for an example afocal zoom optical assembly that is configured in accordance with certain embodiments and is schematically illustrated at FIG. 6.

[0047] Table 3 includes an example optical prescription for an example afocal zoom optical assembly that is configured in accordance with certain embodiments and is schematically illustrated at FIG. 7.

[0048] Table 4 includes an example optical prescription for an example afocal zoom optical assembly that is configured in accordance with certain embodiments and is schematically illustrated at FIG. 8.

[0049] Table 5 includes an example optical prescription for an example afocal zoom optical assembly that is configured in accordance with certain embodiments and is schematically illustrated at FIG. 9.

[0050] Table 6 includes an example optical prescription for an example afocal zoom optical assembly that is configured in accordance with certain embodiments and is schematically illustrated at FIG. 10.

[0051] Table 7 includes an example optical prescription for an example afocal zoom optical assembly that is configured in accordance with certain embodiments and is schematically illustrated at FIG. 11.

[0052] Table 8 includes an example optical prescription for a rear adapter optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 12.

[0053] Table 9 includes an example optical prescription for a rear adapter optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 13.

[0054] Table 10 includes an example optical prescription for a rear adapter optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 14.

[0055] Table 11 includes an example optical prescription for a rear adapter optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 15.

[0056] Table 12 includes an example optical prescription for a rear adapter optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 16.

[0057] Table 13 includes an example optical prescription for a rear adapter optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 17.

[0058] Table 14 includes an example optical prescription for a lens attachment optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 18.

[0059] Table 15 includes an example optical prescription for a lens attachment optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 19.

[0060] Table 16 includes an example optical prescription for a lens attachment finite conjugate optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 20.

[0061] Table 17 includes an example optical prescription for a lens attachment optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 21.

[0062] Table 18 includes an example optical prescription for a lens attachment optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 22.

[0063] Table 19 includes an example optical prescription for a lens attachment optical assembly configured in accordance with the example embodiment that is schematically illustrated at FIG. 23.

[0064] Table 20 includes an example optical prescription for a finite conjugate optical assembly comprising a lens attachment module m124, a core zoom module m224, and a rear adapter module m324 that may be configured in accordance with the example embodiment that is schematically illustrated at FIGS. 24A-24C.

[0065] Table 21 includes an example optical prescription for a finite conjugate optical assembly comprising a lens attachment module m125, a core zoom module m225, and a rear adapter module m325 that may be configured in accordance with the example embodiment that is schematically illustrated at FIGS. 25A-25C.

[0066] Table 22 includes an example optical prescription for a finite conjugate optical assembly comprising a lens attachment module m126, a core zoom module m226, and a rear adapter module m326 that may be configured in accordance with the example embodiment that is schematically illustrated at FIGS. 26A-26C.

[0067] Table 23 includes example embodiments of lens attachments, as in FIG. 27A and/or FIG. 27G, or objectives with long working distance to focal length (WD/FL) ratio, and 16-25 mm diameter external entrance pupils disposed at 50 mm or greater distance.

[0068] Table 24 includes example embodiments of rear adapters or tube lenses, as in FIG. 27A and/or FIG. 27C, with short path length to focal length ratios, 16-25 mm diameter external entrance pupils of 50 mm or greater distance, and an approximate etendue value of 1.58 mm²sr.

[0069] Table 25 includes a zoom field of view matrix in accordance with certain embodiments, representative of the modular system nature of the example embodiments schematically illustrated at FIGS. 27A-27G.

TABLE 1
Table 1: Embodiment 1
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	Infinity
1	Infinity	2.4
2	388.35	2.5	1.497	81.5
3	−62.06	1	1.850	32.3
4	−92.375	0.5
5	97.702	1.8	1.497	81.5
6	1349.45	3
7	Infinity	Zm1			Zm1:	0.500	14.659	26.163	31.886	36.126	37.508
8	−84.35	1	1.595	67.7
9	13.84	2	1.738	32.3
10	23.37	3
11	Infinity	Zm2			Zm2:	69.697	49.483	29.484	19.640	9.736	0.500
12	45.19	1	1.804	39.6
13	24.29	2.284
STO	19.674	3.2	1.487	70.2
15	−16.044	0.939
16	−14.77	1	1.804	39.6
17	−25.146	Zm3			Zm3:	0.500	4.054	11.753	17.680	29.562	47.218
18	−56.309	1	1.607	56.8
19	15.155	1.7	1.728	28.3
20	31.2	Zm4			Zm4:	15.030	17.493	18.189	16.678	10.331	0.446
21	Infinity	3
22	−35.916	1.5	1.691	54.8
23	−52.092	0.5
24	−150.11	4.5	1.603	65.4
25	−15.155	1	1.697	48.5
26	−27.94	0.5
27	Infinity	2.4
IMA	Infinity

TABLE 2
Table 2: Embodiment 2
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	Infinity
1	Infinity	2.5
2	46.34	1.2	1.740	28.3
3	31.72	5	1.439	94.7
4	−228.526	0.5
5	228.526	1.8	1.717	29.5
6	Infinity	3
7	Infinity	Zm1			Zm1:	9.684	18.902	29.333	33.731	38.794	40.334
8	−47.673	1.1	1.618	63.3
9	12.423	2.8	1.749	35.3
10	26.395	3
11	Infinity	Zm2			Zm2:	31.148	21.930	11.499	7.100	2.037	0.498
STO	37.82	2	1.439	94.7
13	−27.352	1.1	1.852	40.8
14	−46.34	Zm3			Zm3:	0.400	0.488	2.659	5.326	13.533	27.375
15	Infinity	2
16	−47.673	1.1	1.618	63.3
17	12.423	2.8	1.749	35.3
18	26.395	Zm4			Zm4:	27.471	27.383	25.212	22.545	14.339	0.496
19	Infinity	3
20	126.6	6.6	1.439	94.7
21	−21.048	1.2	1.786	44.2
22	−29.59	0.5
23	Infinity	2
IMA	Infinity

TABLE 3
Table 3: Embodiment 3
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	Infinity
1	Infinity	2.4
2	108.23	4.8	1.595	67.7
3	−77.5	1	1.720	34.7
4	−259.592	2
5	Infinity	Zm1			Zm1:	0.500	24.673	48.242	61.282	76.910	90.166
6	−34.798	1.5	1.904	31.3
7	−20	1	1.618	63.4
8	57.864	1
9	Infinity	Zm2			Zm2:	33.316	39.214	24.960	12.126	1.053	1.000
10	76.14	1.4	1.517	52.2
11	−86.1	1	1.620	60.3
STO	70.78	Zm3			Zm3:	58.325	18.130	2.500	2.000	1.500	1.000
13	−119.562	1	1.735	48.8
14	74.48	2	1.717	29.5
15	1246.12	Zm4			Zm4:	0.500	10.629	16.941	17.241	13.174	0.500
16	Infinity	2
17	119.14	1	1.747	51.0
18	51.212	6.8	1.595	67.7
19	−32.71	2.7	1.954	32.3
20	−47.21	0.5
21	Infinity	2.4
IMA	Infinity

TABLE 4
Table 4: Embodiment 4
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	Infinity
1	Infinity	2.4
2	135.2191	6	1.497	81.5
3	−81.23256	3	1.804	46.5
4	−579.2985	0.5
5	100.1953	6	1.497	81.5
6	−71.67808	3	1.729	54.7
7	−119.92	Zm1			Zm1:	10.729	30.432	47.364	59.288	70.534	71.656
8	−88.39807	1.9	1.567	42.8
9	−27.90612	1.1	1.595	67.7
10	14.66054	1.9	1.804	39.6
11	23.61669	1
12	Infinity	Zm2			Zm2:	53.224	33.736	17.765	8.952	1.648	0.212
13	27.89249	1.5	1.573	57.7
14	−34.59251	1.1	1.852	40.8
STO	225.5134	Zm3			Zm3:	1.277	0.600	0.500	0.600	9.842	22.504
16	−61.20832	1.1	1.678	55.3
17	8.628543	1.4	1.750	35.0
18	23.21423	Zm4			Zm4:	29.470	29.933	29.071	25.861	12.674	0.335
19	Infinity	1
20	74.38562	2	1.697	55.5
21	38.11623	6.4	1.497	81.6
22	−21.07531	2	1.800	42.2
23	−31.16009	0.5
24	Infinity	2.4
IMA	Infinity

TABLE 5
Table 5: Embodiment 5
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	Infinity
1	Infinity	2.4
2	113.296	3.5	1.497	81.5
3	−504.077	0.5
4	154.500	3.5	1.595	67.7
5	−171.549	1.2	1.720	34.7
6	401.168	2
7	Infinity	Zm1			Zm1:	0.619	23.634	46.431	59.060	74.210	86.962
8	−32.365	1.4	1.904	31.3
9	−20.802	1	1.538	74.7
10	83.958	1	1.755	52.3
11	52.894	2
12	Infinity	Zm2			Zm2:	17.208	41.762	23.536	11.397	0.795	0.349
13	−638.587	1.2	1.548	45.8
14	−53.959	1.1	1.697	55.5
STO	1300.245	Zm3			Zm3:	70.613	10.074	1.723	1.708	1.733	1.500
16	−91.693	1.1	1.755	52.3
17	114.822	3.75	1.717	29.5
18	−862.236	Zm4			Zm4:	0.465	13.431	17.236	16.767	12.160	0.131
19	Infinity	2
20	318.815	4.5	1.497	81.5
21	−72.280	0.5
22	−305.721	6	1.595	67.7
23	−40.649	1.2	1.954	32.3
24	−61.690	0.5
25	Infinity	2.4
IMA	Infinity

TABLE 6
Table 6: Embodiment 6
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	Infinity
1	Infinity	2.5
2	42.042	3	1.773	49.6
3	29.74	8.6	1.439	94.7
4	−55.7	3	1.713	53.9
5	−101.2224	3
6	Infinity	Zm1			Zm1:	25.619	25.844	34.664	47.811	52.668	55.064
7	72.61	5.7	1.613	44.5
8	−20.54	1.2	1.678	55.6
9	28.25	1.5
10	−64.593	1.1	1.678	55.6
11	8.2	2.7	1.720	34.7
12	26.61	3
13	Infinity	Zm2			Zm2:	8.283	40.047	35.039	19.297	8.449	0.500
STO	27.18	3	1.523	51.5
15	−11.3	1.7	1.728	28.3
16	−23.04	Zm3			Zm3:	0.500	8.955	12.151	19.426	25.099	30.541
17	Infinity	2.35
18	−53.49	1.5	1.773	49.6
19	13.84	5	1.501	56.4
20	−11.123	0.4
21	−12.36	1.1	1.618	63.3
22	19.01	3	1.673	32.2
23	324.2	Zm4			Zm4:	52.486	12.043	5.034	0.355	0.672	0.784
24	Infinity	4.5
25	91.12	10.5	1.497	81.6
26	−73.95	0.5
27	516.33	3	1.713	53.9
28	43	12.5	1.439	94.7
29	−148.321	2.5
IMA	Infinity

TABLE 7
Table 7: Embodiment 7
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	Infinity
1	Infinity	2.5
2	54.990	3	1.720	50.6
3	37.559	8.2	1.439	94.7
4	−54.178	3	1.713	53.9
5	−87.440	3
6	Infinity	Zm1			Zm1:	0.500	14.924	26.496	32.507	38.532	38.442
7	−79.56709	3.2	1.586	59.5
8	−18.374	1.1	1.595	67.7
9	19.216	2.7	1.810	40.9
10	35.058	3
11	Infinity	Zm2			Zm2:	40.431	26.006	14.434	8.423	2.398	2.489
STO	80.43011	2	1.439	94.7
13	−24.156	1.7	1.573	57.7
14	−50.488	Zm3			Zm3:	0.300	1.251	5.305	10.669	30.273	43.500
15	Infinity	2.35
16	−108.919	1.5	1.678	55.2
17	17.363	3.8	1.501	56.4
18	−23.497	0.496
19	−25.80029	1.1	1.618	63.3
20	18.607	2.558	1.806	40.9
21	72.384	Zm4			Zm4:	43.898	42.947	38.893	33.529	13.925	0.698
22	Infinity	4.5
23	121.957	3	1.697	55.5
24	71.266	11.8	1.439	94.7
25	−37.03341	3	1.756	45.7
26	−52.25707	2.5
IMA	Infinity

TABLE 8
Table 8: Embodiment 8
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	Infinity
STO	Infinity	95.358
2	Infinity	2.5
3	31.765	5.1	1.439	94.7
4	195.200	1
5	36.470	4	1.595	67.7
6	120.580	1.487
7	24.5	5.4	1.595	67.7
8	555.667	2	1.916	31.6
9	17.760	3.93
10	34.220	5.75	1.689	31.1
11	−21.666	2	1.729	54.1
12	30.2	55.65778
IMA	Infinity

TABLE 9
Table 9: Embodiment 9
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	Infinity
STO	Infinity	95.358
2	Infinity	2.5
3	46.440	6.3	1.439	94.7
4	200.692	0.962
5	35.110	4	1.595	67.7
6	105.440	1.483
7	29.59	6.1	1.595	67.7
8	82.340	2	1.916	31.6
9	20.700	4.772
10	114.310	8	1.689	31.1
11	−26.610	2	1.729	54.1
12	84.24	92.369
IMA	Infinity

TABLE 10
Table 10: Embodiment 10
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	Infinity
STO	Infinity	95.358
2	Infinity	2.5
3	28.580	6	1.439	94.7
4	1400.000	1.000
5	37.740	4.7	1.595	67.7
6	−662.210	1.493
7	120.95	5.4	1.595	67.7
8	266.000	0.908
9	−86.890	2.000	1.916	31.6
10	20.990	2.758
11	27.280	9.1	1.689	31.1
12	−23.207	2.000	1.729	54.1
13	41.63	114.916
IMA	Infinity

TABLE 11
Table 11: Embodiment 11
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	Infinity
STO	Infinity	95.358
2	Infinity	2.5
3	47.545	6.9	1.497	81.5
4	−53.666	2.500	1.613	44.3
5	−491.100	65.63724
6	49.070	5.400	1.626	35.7
7	−17.2	2	1.804	46.6
8	22.200	30.77527
9	−31.890	4.400	1.487	70.2
10	−21.808	67.370
IMA	Infinity

TABLE 12
Table 12: Embodiment 12
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	Infinity
STO	Infinity	117.009
2	Infinity	2.5
3	28.380	13.4	1.439	94.7
4	−37.975	2.5	1.757	47.8
5	−324.937	22.136
6	192.795	5.1	1.541	47.2
7	−38.85269	9.675
8	−19.629	2	1.804	46.6
9	122.956	1.654
10	51.367	3.2	1.699	30.1
11	−1242.590	50.796
IMA	Infinity

TABLE 13
Table 13: Embodiment 13
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	Infinity
STO	Infinity	117.009
2	Infinity	2.5
3	62.543	13.4	1.439	94.9
4	−50.108	2.5	1.757	47.8
5	−119.524	27.128
6	98.365	5.1	1.541	47.2
7	−90.06724	14.917
8	−70.416	2	1.804	46.6
9	48.233	43.830
10	104.507	3.2	1.699	30.1
11	253.408	102.971
IMA	Infinity

TABLE 14
Table 14: Embodiment 14
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	32
1	Infinity	1.5
2	−208.953	7.5	1.618	63.3
3	−57.260	0.997
4	43.200	16.5	1.497	81.5
5	−44.732	3.455
6	−33.373	2.5	1.720	50.6
7	277.160	16	1.497	81.5
8	−34.417	1
9	121.232	2.5	1.847	23.8
10	48.006	12.4	1.497	81.5
11	−69.746	5.5
12	−30.9	2.5	1.638	42.4
13	−481	1.7
14	−739.9	5	1.923	20.9
15	−77.27	105.5
16	Infinity	—

TABLE 15
Table 15: Embodiment 15
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	92.60424
1	Infinity	1.5
2	−1645.000	2.4	1.916	31.6
3	80.500	9.9	1.439	94.7
4	−56.890	1.491
5	65	19.2	1.801	35.0
6	−69.882	2.2	1.638	42.4
7	36.350	7.2	1.439	94.7
8	202.510	105.5
9	Infinity	—

TABLE 16
Table 16: Embodiment 16
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	109.9136
1	Infinity	2.5
2	121.856	2.5	1.673	38.3
3	97.190	8.2	1.700	48.1
4	−74.647	1.5
5	−70	2.5	1.741	52.6
6	43.640	1.5
7	42.194	14.8	1.497	81.5
8	−30.699	4.6	1.729	54.1
9	−48.740	105.5
10	Infinity	—

TABLE 17
Table 17: Embodiment 17
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	187.4364
1	Infinity	3
2	199.700	12	1.439	94.9
3	−32.944	2.5	1.700	48.1
4	−68.562	1
5	−121.111	5.5	1.620	36.4
6	−46.239	2.192
7	−54.448	2.5	1.613	44.5
8	−189.507	105.5
9	Infinity	—

TABLE 18
Table 18: Embodiment 18
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	394.6556
1	Infinity	1.5
2	132.530	12	1.439	94.9
3	−80.418	2.75	1.694	53.2
4	120.815	1
5	58.41	10	1.693	52.9
6	58.922	2
7	164.260	4.6	1.609	46.6
8	−153.000	105.5
9	Infinity	—

TABLE 19
Table 19: Embodiment 19
Surf	Radius	Thickness	Glass Nd	Glass vd
OBJ	Infinity	130.752
1	Infinity	3
2	279.767	15	1.516	64.1
3	−215.149	148.5053
4	−103.519	3.5	1.729	54.7
5	141.751	40.90274
6	−53.354	2.2	1.697	55.5
7	84.129	8.2	1.439	94.7
8	−49.677	0.9969684
9	111.665	6.9	1.518	58.9
10	−68.612	105.5
11	Infinity	—

TABLE 20
Table 20: Embodiment 20
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag.3	Mag. 4	Mag. 5	Mag.6
OBJ	Infinity	187.436
1	Infinity	3
2	199.7	12	1.439	94.9
3	−32.944	2.5	1.700	48.1
4	−68.562	1
5	−121.111	5.5	1.620	36.4
6	−46.239	2.192
7	−54.448	2.5	1.613	44.5
8	−189.507	51
9	Infinity	2.5
10	46.34	1.2	1.740	28.3
11	31.72	5	1.439	94.7
12	−228.526	0.5
13	228.526	1.8	1.717	29.5
14	Infinity	3
15	Infinity	Zm1			Zm1:	9.684	18.902	29.333	33.731	38.794	40.334
16	−47.673	1.1	1.618	63.3
17	12.423	2.8	1.749	35.3
18	26.395	3
19	Infinity	Zm2			Zm2:	31.148	21.930	11.499	7.100	2.037	0.498
STO	37.82	2	1.439	94.7
21	−27.352	1.1	1.852	40.8
22	−46.34	Zm3			Zm3:	0.400	0.488	2.659	5.326	13.533	27.375
23	Infinity	2
24	−47.673	1.1	1.618	63.3
25	12.423	2.8	1.749	35.3
26	26.395	Zm4			Zm4:	27.471	27.383	25.212	22.545	14.339	0.496
27	Infinity	3
28	126.6	6.6	1.439	94.7
29	−21.048	1.2	1.786	44.2
30	−29.59	5
31	46.44	6.3	1.439	94.7
32	200.692	0.962
33	35.11	4	1.595	67.7
34	105.44	1.483
35	29.59	6.1	1.595	67.7
36	82.34	2	1.916	31.6
37	20.7	4.768
38	114.31	8	1.689	31.1
39	−26.61	2	1.729	54.1
40	84.24	92.3718
IMA	Infinity

TABLE 21
Table 21: Embodiment 21
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	92.604
1	Infinity	1.5
2	−1645	2.4	1.916	31.6
3	80.5	9.9	1.439	94.7
4	−56.89	1.491
5	65	19.2	1.801	35.0
6	−69.882	2.2	1.638	42.4
7	36.35	7.2	1.439	94.7
8	202.51	51
9	Infinity	2.5
10	46.34	1.2	1.740	28.3
11	31.72	5	1.439	94.7
12	−228.526	0.5
13	228.526	1.8	1.717	29.5
14	Infinity	3
15	Infinity	Zm1			Zm1:	9.684	18.902	29.333	33.731	38.794	40.334
16	−47.673	1.1	1.618	63.3
17	12.423	2.8	1.749	35.3
18	26.395	3
19	Infinity	Zm2			Zm2:	31.148	21.930	11.499	7.100	2.037	0.498
STO	37.82	2	1.439	94.7
21	−27.352	1.1	1.852	40.8
22	−46.34	Zm3			Zm3:	0.400	0.488	2.659	5.326	13.533	27.375
23	Infinity	2
24	−47.673	1.1	1.618	63.3
25	12.423	2.8	1.749	35.3
26	26.395	Zm4			Zm4:	27.471	27.383	25.212	22.545	14.339	0.496
27	Infinity	3
28	126.6	6.6	1.439	94.7
29	−21.048	1.2	1.786	44.2
30	−29.59	5
31	46.44	6.3	1.439	94.7
32	200.692	0.962
33	35.11	4	1.595	67.7
34	105.44	1.483
35	29.59	6.1	1.595	67.7
36	82.34	2	1.916	31.6
37	20.7	4.768
38	114.31	8	1.689	31.1
39	−26.61	2	1.729	54.1
40	84.24	92.372
IMA	Infinity

TABLE 22
Table 22: Embodiment 22
Surf	Radius	Thickness	Glass Nd	Glass vd		Mag. 1	Mag. 2	Mag. 3	Mag. 4	Mag. 5	Mag. 6
OBJ	Infinity	32.000
1	Infinity	1.500
2	−208.953	7.500	1.618	63.3335
3	−57.26	0.997
4	43.2	16.500	1.497	81.5459
5	−44.732	3.455
6	−33.373	2.5	1.72003	50.6222
7	277.16	16	1.497	81.5
8	−34.417	1
9	121.232	2.5	1.84666	23.8
10	48.006	12.4	1.497	81.5
11	−69.746	5.5
12	−30.9	2.5	1.638	42.4
13	−481	1.7
14	−739.9	5	1.92286	20.9
15	−77.27	51
16	Infinity	2.5
17	46.34	1.2	1.74	28.3
18	31.72	5	1.439	94.7
19	−228.526	0.5
20	228.526	1.8	1.71736	29.5
21	Infinity	3
22	Infinity	Zm1			Zm1:	9.684	18.902	29.333	33.731	38.794	40.334
23	−47.673	1.1	1.618	63.3
24	12.423	2.8	1.7495	35.3
25	26.395	3
26	Infinity	Zm2			Zm2:	31.148	21.930	11.499	7.100	2.037	0.498
STO	37.82	2	1.43875	94.7
28	−27.352	1.1	1.8515	40.8
29	−46.34	Zm3			Zm3:	0.400	0.488	2.659	5.326	13.533	27.375
30	Infinity	2
31	−47.673	1.1	1.618	63.3
32	12.423	2.8	1.7495	35.3
33	26.395	Zm4			Zm4:	27.471	27.383	25.212	22.545	14.339	0.496
34	Infinity	3
35	126.6	6.6	1.43875	94.7
36	−21.048	1.2	1.786	44.2
37	−29.59	5
38	47.545	6.9	1.497	81.5
39	−53.666	2.5	1.6134	44.3
40	−491.1	65.6372
41	49.07	5.4	1.626	35.7
42	−17.2	2	1.804	46.6
43	22.2	30.7753
44	−31.89	4.4	1.487	70.2
45	−21.808	67.370
IMA	Infinity

TABLE 23
Part #	Description	F1(mm)	W.D. (mm)	W.D./F1
1-81201	0.25X	400	356	0.89
1-81202	0.5X	200	174	0.87
1-81203	0.75X	133.33	100	0.75
1-81204	1X	100	90	0.9
1-81205	1.25X	80	72	0.9
1-81206	1.5X	65	45	0.69
1-81207	2X	50	30	0.6

TABLE 24
			Sensor Diag	total barrel	Path Length D3	Focal Length F3
Part #	Desc.	Format	(Dim C) (mm)	track (mm)	(Dim. B) (mm)	( Dim. A) (mm)	D3/F3 ratio
1-81101	0.6875×	⅔″	11	45.9	95	110	0.864
1-81102	1×	1″	16	66.3	117.5	160	0.734
1-81103	1.375×	4/3″	22	100.8	147.5	220	0.67
1-81104	2×	32 mm	32	101	192.5	320	0.602
1-81105	2.75×	Full Frame	44	125	248.909	440	0.566
1-81106	3.375×	54 mm	54	150	295.559	540	0.547
1-81107	4×	64 mm	64	175	342.209	640	0.535

TABLE 25
Resolv4K Zoom Field of View Matrix
		Rear Adapter Mag
		0.6875×	1×	1.375×	2×
		Ideal Camera Format
		⅔″	1″	4/3″	32 mm (APS)
		Pixel Resolution (μm)
		2.24	5.47	3.26	7.95	4.48	10.93	6.51	15.90	Resolution
Lens	W.D.										Limit	DOF
Attachment	(mm)	Format	Low	High	Low	High	Low	High	Low	High	(μm)	(mm)
0.25	1-81201	Mag. (×)	0.110	0.773	0.160	1.125	0.220	1.547	0.320	2.250
NA Low		½″	72.73	10.34	50.00	7.11	36.36	5.17	25.00	3.56	Low	Low
0.0082		⅔″	100.0	14.22	68.75	9.78	50.00	7.11	34.38	4.89	40.85	7.41
NA High	359.5	1″	—	—	100.0	14.22	72.73	10.34	50.00	7.11	High	High
0.0238		4/3″	—	—	—	—	100.0	14.22	68.75	9.78	14.13	0.89
		32 mm	—	—	—	—	—	—	100.0	14.22
0.5	1-81202	Mag. (×)	0.220	1.547	0.320	2.250	0.440	3.094	0.640	4.500
NA Low		½″	36.36	5.17	25.00	3.56	18.18	2.59	12.50	1.78	Low	Low
0.0164		⅔″	50.00	7.11	34.38	4.89	25.00	3.56	17.19	2.44	20.43	1.85
NA High	173	1″	—	—	50.00	7.11	36.36	5.17	25.00	3.56	High	High
0.0475		4/3″	—	—	—	—	50.00	7.11	34.38	4.89	7.06	0.22
		32 mm	—	—	—	—	—	—	50.00	7.11
0.75	1-81203	Mag. (×)	0.330	2.320	0.480	3.375	0.660	4.641	0.960	6.750
NA Low		½″	24.24	3.45	16.67	2.37	12.12	1.72	8.33	1.19	Low	Low
0.0246		⅔″	33.33	4.74	22.92	3.26	16.67	2.37	11.46	1.63	13.62	0.82
NA High	110	1″	—	—	33.33	4.74	24.24	3.45	16.67	2.37	High	High
0.0713		4/3″	—	—	—	—	33.33	4.74	22.92	3.26	4.71	0.10
		32 mm	—	—	—	—	—	—	33.33	4.74
1	1-81204	Mag. (×)	0.440	3.094	0.640	4.500	0.880	6.188	1.280	9.000
NA Low		½″	18.18	2.59	12.50	1.78	9.09	1.29	6.25	0.89	Low	Low
0.03285		⅔″	25.00	3.56	17.19	2.44	12.50	1.78	8.59	1.22	10.21	0.46
NA High	90	1″	—	—	25.00	3.56	18.18	2.59	12.50	1.78	High	High
0.095		4/3″	—	—	—	—	25.00	3.56	17.19	2.44	3.53	0.055
		32 mm	—	—	—	—	—	—	25.00	3.56
1.25	1-81205	Mag. (×)	0.550	3.867	0.800	5.625	1.100	7.734	1.600	11.25
NA Low		½″	14.55	2.07	10.00	1.42	7.27	1.03	5.00	0.71	Low	Low
0.0411		⅔″	20.00	2.84	13.75	1.96	10.00	1.42	6.88	0.98	8.17	0.30
NA High	72	1″	—	—	20.00	2.84	14.55	2.07	10.00	1.42	High	High
0.1188		4/3″	—	—	—	—	20.00	2.84	13.75	1.96	2.83	0.035
		32 mm	—	—	—	—	—	—	20.00	2.84
1.5	1-81206	Mag. (×)	0.660	4.641	0.960	6.750	1.320	9.281	1.920	13.50
NA Low		½″	12.12	1.72	8.33	1.19	6.06	0.86	4.17	0.59	Low	Low
0.0493		⅔″	16.67	2.37	11.46	1.63	8.33	1.19	5.73	0.81	6.81	0.206
NA High	46.5	1″	—	—	16.67	2.37	12.12	1.72	8.33	1.19	High	High
0.1425		4/3″	—	—	—	—	16.67	2.37	11.46	1.63	2.35	0.025
		32 mm	—	—	—	—	—	—	16.67	2.37
2	1-81207	Mag. (×)	0.880	6.188	1.280	9.000	1.760	12.38	2.560	18.00
NA Low		½″	9.09	1.29	6.25	0.89	4.55	0.65	3.13	0.44	Low	Low
0.0657		⅔″	12.50	1.78	8.59	1.22	6.25	0.89	4.30	0.61	5.11	0.116
NA High	32	1″	—	—	12.50	1.78	9.09	1.29	6.25	0.89	High	High
0.1900		4/3″	—	—	—	—	12.50	1.78	8.59	1.22	1.77	0.014
		32 mm	—	—	—	—	—	—	12.50	1.78
UltraZoom
2	1-55075	Mag. (×)	0.880	6.188	1.280	9.000	1.760	12.38	2.560	18.00
NA Low	Nav 4×	½″	8.10	1.29	6.25	0.89	4.55	0.65	3.13	0.44	Low	Low
0.0657		⅔″	8.10	1.78	8.10	1.22	6.25	0.89	4.30	0.61	5.11	116
NA High	20	1″	—	—	8.10	1.78	8.10	1.29	6.25	0.89	High	High
0.1900		4/3″	—	—	—	—	8.10	1.78	8.10	1.22	1.77	14
		32 mm	—	—	—	—	—	—	8.10	1.78
3		Mag. (×)	1.320	9.281	1.920	13.50	2.640	18.56	3.840	27.00
NA Low	Nav 6×	1/2″	6.06	0.86	4.17	0.59	3.03	0.43	2.08	0.30	Low	Low
0.0986		⅔″	6.25	1.19	5.73	0.81	4.17	0.59	2.86	0.41	3.40	51
NA High	25	1″	—	—	6.25	1.19	6.06	0.86	4.17	0.59	High	High
0.2850		4/3″	—	—	—	—	6.25	1.19	5.73	0.81	1.18	6.2
		32 mm	—	—	—	—	—	—	6.25	1.19
5	1-55227	Mag. (×)	2.200	15.47	3.200	22.50	4.400	30.94	6.400	45.00
NA Low	Nav 10×	½″	3.20	0.52	2.50	0.36	1.82	0.26	1.25	0.18	Low	Low
0.1643		⅔″	3.20	0.71	3.20	0.49	2.50	0.36	1.72	0.24	2.04	19
NA High	10	1″	—	—	3.20	0.71	3.20	0.52	2.50	0.36	High	High
0.4000		4/3″	—	—	—	—	3.20	0.71	3.20	0.49	0.84	3.1
		32 mm	—	—	—	—	—	—	3.20	0.71
10		Mag. (×)	4.400	30.94	6.400	45.00	8.800	61.88	12.80	90.00
NA Low	Nav 20×	½″	1.25	0.26	1.25	0.18	0.91	0.13	0.63	0.09	Low	Low
0.3285		⅔″	1.25	0.36	1.25	0.24	1.25	0.18	0.86	0.12	1.02	4.6
NA High	10	1″	—	—	1.25	0.36	1.25	0.26	1.25	0.18	High	High
0.5300		4/3″	—	—	—	—	1.25	0.36	1.25	0.24	0.63	1.8
		32 mm	—	—	—	—	—	—	1.25	0.36

[0070] A finite conjugate camera, optical assembly, lens assembly, and/or digital microscope includes a modular optical assembly or a modular lens system. Several example embodiments are described herein that are capable of providing a range of numerical apertures or NAs across numerous sensor format sizes as well as providing zooming capability. A lens system in accordance with certain embodiments may have an advantageous amount of etendue capability, defined as the product of the pupil area and the solid angle of the field of view [Smith—Modern Optical Engineering, pg. 716, the entire book is incorporated by reference]. [Etendue=π*A*sin²θ] Eq. 1 [Bentley & Olson—Field Guide to Lens Design, pg. 120, the entire book is incorporated by reference], for a flat surface with a uniform solid angle, where A is the area of the surface and θ is the half angle of the marginal ray.

[0071] An optical design of a lens having approximate etendue of 0.95 mm²sr or greater is provided that is configured to approximately fully utilize a 6.6 MP sensor having a roughly 4:3 aspect ratio. A similarly designed optical system having an approximate etendue value of 4.65 mm²sr is provided that is configured to approximately fully utilize a 32 MP sensor having roughly a 4:3 aspect ratio. Lens etendue system values of between approximately 0.95 to 4.65 mm²sr are provided in certain embodiments of optical assemblies that are configured to approximately reach sensor limited performance on various aspect ratios of digital or analog capturing devices with 4075 to 8194 individual sensing units across the diagonal diameter of the device. These individual sensing units are commonly referred to as pixels in digital cameras. Multiple embodiments and examples are described that include etendue preserving lens systems that incorporate a ratio of highest to lowest magnification of at least 5.5:1 and have etendue values of between about 0.95 to 4.65 mm²sr.

[0072] The ratio of the highest magnification possible (M1) to the lowest magnification possible (M2) is advantageous in several different embodiments of zoom lens systems that can move continuously between the high and low magnification positions, therefore providing any magnification between the high and low values. This feature is also advantageous in embodiments including zoom lens systems that may have a continuous movement with discrete stops for specific repeatable magnification selections inside advantageous high and low magnification values.

[0073] A modular finite conjugate lens assembly is provided that includes a zooming component. The lens assembly is configured to exhibit between 0.95 and 4.65 mm²sr of etendue, and a ratio of highest to lowest magnification between 5.5:1 and 16:1. The lens assembly may exhibit a magnification 2× or more at one or more points of the zoom.

[0074] Another modular finite conjugate lens assembly is provided that includes an afocal zooming component. The lens assembly is configured to exhibit between 0.95 and 4.65 mm²sr of etendue, and a ratio of highest to lowest magnification between 5.5:1 and 16:1.

[0075] Another finite conjugate lens assembly is provided that includes modular interchangeable components, including a zooming component that includes three independently movable lens groups that are disposed within the lens assembly between a pair of static lens groups, and wherein the lens assembly exhibits an etendue of between 0.95 and 4.65 mm²sr.

[0076] In certain embodiments, the lens assembly may be configured to have a resolving power such that 4,075 to 8,194 individual pixels are resolvable across a diagonal of an image plane.

[0077] In certain embodiments, the lens assembly exhibits an etendue between 0.95 and 4.65 mm²sr at any point of the zoom range.

[0078] In certain embodiments, the lens assembly may be configured to exhibit between 1.57 and 4.65 mm²sr of etendue, and a ratio of highest to lowest magnification between 7:1 and 16:1.

[0079] In certain embodiments, the lens assembly may be configured to exhibit between 2.88 and 4.65 mm²sr of etendue, and a ratio of highest to lowest magnification between 6.2:1 and 16:1.

[0080] In certain embodiments, the lens assembly may include a lens attachment module coupled to face an object side of the zooming component within the lens assembly. The lens attachment module may include two or more fixed focal length lens elements, and may have a positive focal length, and may exhibit a pupil size between 16 and 25 mm and/or a pupil depth of 50 mm or greater. The two or more fixed focal length lens elements of the lens attachment module may include a doublet. The two or more fixed focal length lens elements of the lens attachment module may further include a triplet and/or a second doublet and one or more singlets and/or multiple singlets.

[0081] In certain embodiments, the lens assembly may include a rear adapter module coupled to face an image side of the zooming component within the lens assembly. The rear adapter module may include three or more fixed focal length lens elements, and may have a positive focal length, and may exhibit a pupil size between 16 and 25 mm and/or a pupil depth of 50 mm or greater. The three or more fixed focal length lens elements of the rear adapter module may include two doublets and a singlet, or a doublet and three singlets.

[0082] The lens assembly may include a core zoom module including the zooming component, and one or both of a lens attachment module and a rear adapter module.

[0083] Another modular finite conjugate lens assembly is provided that includes a zooming component that is configured to exhibit at least 1.58 mm²sr of etendue at a lowest magnification position, and a ratio of highest to lowest magnification of at least 7:1. In certain embodiments, the lens assembly may provide a maximum magnification of 2× or greater. The lens assembly may be configured to have a resolving power such that greater than 4,075 individual pixels are resolvable across a diagonal of an image plane. The etendue of the lens assembly may be between 1.58 and 4.95 mm²sr at one or more points or at any point of a zoom range of the zooming component. The ratio of highest to lowest magnification may be between 7:1 and 16:1.

[0084] The lens assembly may include an afocal zooming component. The lens assembly may include a lens attachment module that is coupled at an object end of the afocal zooming component within the lens assembly. The lens attachment module may include two or more fixed focal length lens elements, and may have a positive focal length, and may exhibit a pupil size of between 16 and 25 mm. The lens attachment module may exhibit a pupil depth of 75 mm or greater.

[0085] The lens assembly may include a rear adapter module that is coupled at an image end of an afocal zooming component within the lens assembly. The rear adapter module may include three or more fixed focal length lens elements, and may have a positive focal length, and may exhibit a pupil size of between 16 and 25 mm. The rear adapter module may exhibits a pupil depth of 75 mm or greater.

[0086] The lens assembly may include an afocal zoom section that includes the zooming component.

[0087] The lens assembly may include a core zoom module including the zooming component; a lens attachment module and a rear adapter module. The lens attachment module may include two or more fixed focal length lens elements. The lens attachment module may be coupled to an object end of the core zoom module and may have a positive focal length. The rear adapter module may include three or more fixed focal length lens elements. The rear adapter module may be coupled to an image end of the core zoom module and may have a positive focal length. The lens assembly may exhibit a pupil depth of at least 75 mm or a pupil size between 16 and 25 mm, or both.

[0088] In certain embodiments, the lens assembly may be configured such that a wavelength focus position across a wavelength range from 430 nm to 1100 nm differs by not more than 3× from a DOF (depth of field) at 550 nm light from a same 550 nm light focus position, wherein DOF is defined as

$\mathrm{DOF}=\pm \frac{\lambda }{2*N{A}^2},$

where λ is wavelength and NA is Numerical Aperture.

[0089] The lens assembly may be configured such that a wavelength focus position across a wavelength range from 430 nm to 660 nm differs by not more than 1× from the DOF (depth of focus) at 550 nm light from a same 550 nm light focus position, wherein DOF is defined as

$DOF=\pm \frac{\lambda }{2*{\mathrm{NA}}^2},$

where λ is wavelength and NA is Numerical Aperture.

[0090] The lens assembly may be configured such that a wavelength focus position across a wavelength range from 900 nm to 1700 nm differs by not more than 3× from the DOF (depth of focus) at 1200 nm light from a same 1200 nm light focus position, wherein DOF is defined as

$\mathrm{DOF}=\pm \frac{\lambda }{2*N{A}^2},$

where λ is wavelength and NA is Numerical Aperture.

[0091] A lens assembly in accordance with certain embodiments may include a core zoom module that includes the zooming component, a lens attachment module coupled at an object end of the core zoom module, and a rear adapter module coupled at an image end of the core zoom module.

[0092] In certain embodiments, a lens assembly may include an afocal zooming component. The lens assembly may include an afocal zoom module including the afocal zooming component. A lens attachment module may be coupled at an object side of the afocal zoom module within the lens assembly. A rear adapter module may be coupled at an image side of the afocal zoom module within the lens assembly. The lens assembly may include one or more of a motorization module, a lighting module, a focusing module, a mount module, a sensor module, a processing module, and an interface module.

[0093] In certain embodiments, a zooming component may include five lens groups including, from object side to image side of the lens assembly, a positive focal length group, a negative focal length group, a third group, another negative focal length group, and another positive focal length group. The third group may be positive or negative.

[0094] In certain embodiments, the zooming component may include five lens groups including, from object side to image side of the lens assembly, a static first group, a movable second group, a third group, a movable fourth group, and a static fifth group. The third group may include a movable group. The movable second and fourth groups may have a same sign of optical power, and a movable third group may have a same or opposite sign of optical power as the movable second and fourth groups. The third group may include a static group.

[0095] In certain embodiments, the zooming component may include five lens groups including, from object side to image side of the lens assembly, a static positive group, a negative movable group, a positive static group, a negative movable group, and a positive static group.

[0096] In certain embodiments, the zooming component may include five lens groups including, from object side to image side of the lens assembly, a static positive group, a negative movable group, a positive movable group, a negative movable group, and a static positive group.

[0097] In certain embodiments, the zooming component may include five lens groups including, from object side to image side of the lens assembly, a static positive group, a negative movable group, a negative movable group, a negative movable group, and a positive static group.

[0098] In certain embodiments, the zooming component may include three movable groups. The three movable groups may be disposed consecutively within the lens assembly. The three movable groups may be disposed between a pair of static groups within the lens assembly.

[0099] In certain embodiments, the zooming component may include five lens groups including, from object side to image side of the lens assembly, a static group, a movable triplet, a third group, a movable doublet, and another static group. The third group may include a doublet. The third group may be static or movable.

[0100] In certain embodiments, the zooming component may include, from object side to image side of the lens assembly, a static group, a positive movable group, another movable group, another positive movable group, and another static group. The zooming component may include three consecutive independently movable positive lens groups. The three consecutive independently movable lens groups may include an independently movable negative lens group disposed between a pair of independently movable positive lens groups.

[0101] A lens assembly may be configured such that a telecentric chief ray value at an object is less than 2° relative to a flat perpendicular object when combined with the zooming component.

[0102] A lens attachment module including a lens attachment lens assembly is also provided herein. The lens attachment module is configured for coupling with a zoom module for use as part of a zoom lens system. The lens attachment lens assembly includes two or more lens elements and has a positive focal length. The lens attachment lens assembly is configured to exhibit a pupil size of between 16 and 25 mm and a pupil depth greater than 50 mm.

[0103] In certain embodiments, the lens attachment lens assembly may exhibit an etendue between 0.95 and 4.65 mm²sr and may be configured to work in conjunction with said zoom module with 50% or less vignetting through a zoom range of the zoom module.

[0104] In certain embodiments, the lens attachment lens assembly may exhibit a pupil depth that is greater than 75 mm. The lens assembly may be configured such that pupil aberrations are matched to the zoom module to reduce system aberration, thereby improving system performance.

[0105] In certain embodiments, the lens attachment module may be configured for coupling at an object end of a zoom module that also has a rear adapter module coupled at an image end within the lens assembly. The lens assembly may also include one or more of a motorization module, a lighting module, a focusing module, a mount module, a sensor module, a processing module, and an interface module coupled together within said lens assembly.

[0106] In certain embodiments, two or more lens elements of the lens attachment lens assembly may include a doublet, and either a triplet; a second doublet and a singlet; and/or two or three singlets.

[0107] A rear adapter module including a rear adapter lens assembly is also provided herein. The rear adapter module is configured for coupling with a zoom module for use as part of a zoom lens system. The rear adapter lens assembly includes three or more lens elements and has a positive focal length. The rear adapter lens assembly is configured to exhibit a pupil size of between 16 and 25 mm and a pupil depth greater than 50 mm.

[0108] In certain embodiments, the rear adapter lens assembly may be configured to exhibit between 0.95 and 4.65 mm²sr. The rear adapter lens assembly may be configured to work in conjunction with a zoom module with 50% or less vignetting through a zoom range of the zoom module.

[0109] In certain embodiments, the rear adapter lens assembly may exhibit a pupil depth that is greater than 75 mm. The rear adapter lens assembly may be configured such that pupil aberrations are matched to the zoom module to reduce system aberration, thereby improving system performance.

[0110] In certain embodiments, the rear adapter module may be coupled at an image end of a zoom module that also has a lens attachment module coupled at an object end. One or more of a motorization module, a lighting module, a focusing module, a mount module, a sensor module, a processing module, and an interface module may also be coupled together within the lens assembly.

[0111] In certain embodiments, the rear adapter lens assembly of the rear adapter module may include a doublet and three or more singlets, or two doublets and one or more singlets.

[0112] A finite conjugate camera is also provided including a finite conjugate lens assembly, e.g., as set forth at any of the example embodiments described herein; an image sensor disposed at an image plane of the optical assembly for capturing images; and a display or interface for communicating with an external display, or both, for displaying the images captured at the image sensor. The finite conjugate camera may be configured as a digital microscope.

[0113] A finite conjugate camera is also provided including a finite conjugate lens assembly, e.g., as set forth at any of the example embodiments described herein; and an eyepiece configured and positioned such that images produced by the optical assembly are viewable by looking through the eyepiece. The finite conjugate camera may be configured as a microscope.

[0114] Another finite conjugate camera is provided that includes:

• • [0115] (a) an afocal zoom module including a zoom lens assembly including five lens groups including, from object end to image end (i) a first positive static group including a doublet, a triplet, two doublets, or a doublet and a singlet; (ii) a first negative movable group including a triplet, or one or two doublets, or a doublet and a singlet; (iii) a third group including a doublet, or a triplet, or three singlets, or a doublet and a singlet; (iv) a second negative movable group including one or two doublets, or a triplet, or a doublet and a singlet; and (v) a second positive static group including a triplet, a doublet, or a doublet and a singlet, or two doublets;
  • [0116] (b) a lens attachment module coupled to the object end of the zoom module, wherein the lens attachment module comprises a lens attachment lens assembly including (i) a doublet and a triplet, or (ii) two doublets and a singlet, or (iii) a doublet and three singlets, or (iv) a doublet and two singlets, or (v) three doublets, or (vi) three doublets and a singlet; or (vii) a triplet and a doublet and a singlet, or (viii) a triplet and two doublets, or (ix) two doublets and three singlets, or (x) two doublets and four singlets;
  • [0117] (c) a rear adapter module coupled to an image end of the zoom module, wherein the rear adapter module comprises a rear adapter lens assembly including (i) one doublet and three singlets, or (ii) two doublets and a singlet; and
  • [0118] (d) an image sensor or eyepiece disposed at an image plane.

[0119] Another finite conjugate camera is provided, including, from object end to image end:

• • [0120] (a) a lens attachment module that comprises a lens attachment lens assembly including (i) a doublet and a triplet, or (ii) a doublet with two or more singlets, or (iii) two doublets and one or more singlets;
  • [0121] (b) an afocal zoom module exhibiting a ratio of highest to lowest magnification between 5.5:1 and 16:1 and an etendue between 0.95 and 4.65 mm²sr, and including a zoom lens assembly including (i) a first positive focal length static group including a triplet or a doublet and a singlet; (ii) a first negative focal length movable group including a triplet, or one or two doublets, or a doublet and a singlet; (iii) a third static or movable group including a doublet, or a triplet, or three singlets; (iv) a second negative focal length movable group including one or two doublets, or a doublet and a singlet; and (v) a second positive focal length static group including a triplet, a doublet, or a doublet and a singlet;
  • [0122] (c) a rear adapter module that comprises a rear adapter lens assembly including (i) a doublet and three singlets, or (ii) two doublets and a singlet, or (iii) two doublets and two singlets, or (iv) a doublet and four singlets; and
  • [0123] (d) an image sensor or eyepiece disposed at an image plane.

[0124] Optical assemblies in accordance with certain embodiments may include a zooming component that is configured such that a ratio of highest to lowest magnification is within a range between 5.5:1 and 16:1. Example embodiments of the optical layout of a finite conjugate camera or microscope are schematically illustrated in FIGS. 24A-24C, 25A-25C, and 26A-26C. A finite conjugate optical assembly is typically used to image objects that are disposed at distances of less than 21 times the focal length of the optical assembly. A finite conjugate optical assembly may be combined with an image sensor to form a finite conjugate camera or an eyepiece may be used to view objects with the naked eye. A finite conjugate camera may include a display, a processor, memory for storing images, and wired and/or wireless communications interfaces for receiving and/or transmitting image data.

[0125] Several example embodiments are provided of optical assemblies that include one of a multitude of positive focal length lens attachment options, which may be provided as a lens attachment module m1 as in FIG. 27A, or module m124, module m125 or module m126 as in the example embodiments that are schematically illustrated at FIGS. 24A-24C, 25A-25C or 26A-26C, respectively. Further example lens attachment modules are described herein with reference to FIGS. 18-23 and Tables 14-19, including examples of first lens groups G114-G122, respectively, wherein the “first” lens group is disposed between the object and the other six lens groups, i.e., closest to the object of the seven lens groups, and disposed on the object end of the core zoom module m2 as in FIG. 27A, or module m224, module m225 or module m226 as in FIGS. 24A-24C, 25A-25C and 26A-26C, respectively. Further example lens attachment modules are described herein with reference to FIG. 27G, including example lens attachment modules m127, m128, m129, m130, m131, m132 and m133 which may be configured in accordance with any of the examples set forth at Table 23. Optical assemblies in accordance with certain lens attachment embodiments may resemble large field of view (FOV) microscope objectives. A lens attachment module m1 as in FIG. 27A may be configured in certain embodiments to allow varying working distances, object NA values, fields of view, and/or telecentricity levels.

[0126] Several example embodiments are also provided of optical assemblies that include a zooming component, or core zoom module m2 as in FIG. 27A, including the example core zoom modules m224, m225, and m226 of the example embodiments that are schematically illustrated at FIGS. 24A-24C, 25A-25C or 26A-26C, respectively, and described at Tables 20-22. Further example zoom modules are described herein with reference to FIGS. 5A-11C, and Tables 1-7. Each of the example zoom modules of FIGS. 5A-11C and 24A-26C, respectively include, from object end to image end of the optical assembly, a second lens group G201-G207 and G220-G222, a third lens group G301-G307 and G320-G322, a fourth lens group G401-G407 and G420-G422, a fifth lens group G501-G507 and G520-G522, and a sixth lens group G601-G607 and G620-G622. Further zoom module examples are described herein with reference to FIG. 27E including examples of core zoom modules m227, m228, m229, m230 and m231. Zoom modules m2 as in FIG. 27A in accordance with certain embodiments include afocal zoom modules and provide ratios of highest to lowest magnification between 5.5:1 and 16:1.

[0127] Several example embodiments are also provided of optical assemblies that include one of a multitude of positive focal length rear adapter options, which may be provided as a rear adapter module m3 as in FIG. 27A, or as module m324, module m325 or module m326 of the example embodiments that are described herein with reference to FIGS. 24A-24C, 25A-25C or 26A-26C, respectively, and Tables 20-22, wherein the rear adapter module m324 of FIGS. 24A-24C includes a seventh lens group G720 which is disposed between the core zoom module and the image plane, and rear adapter module m325 of FIGS. 25A-25C includes lens group G721, and rear adapter module m326 of FIGS. 26A-26C includes lens group G722. Further examples of rear adapter modules are described herein with reference to FIGS. 12-17 and Tables 8-13, including example seventh lens groups G708-G713, respectively. Further example rear adapter modules m327, m328, m329 and m330 are schematically illustrated at FIG. 27C and may be configured in accordance with any of the examples set forth at Table 24. Rear adapter optical assemblies in accordance with certain embodiments may include or resemble tube lenses. A rear adapter module m3 as in FIG. 27A may be configured in certain embodiments to allow varying sensor size coverage and sensor side NA values.

[0128] The optical assembly that is schematically illustrated at FIGS. 4A-4C does not have separate modules, and instead has static groups G10 and G20 and G60 and G70 as included groups, along with groups G30 and G50 (but not G40) within a single lens assembly. Each of the six lens groups G10, G20, G30, G50, G60 and G70 of the optical assembly of FIGS. 4A-4C consists of one doublet, such that the optical assembly of FIGS. 4A-4C consists of six doublets, wherein the first doublet includes a convex meniscus lens coupled to a biconvex lens as lens group G10, the second doublet includes a biconvex lens coupled to a concave meniscus lens as lens group G20, the third doublet includes a concave meniscus lens coupled to a biconcave lens as lens group G30, a fourth doublet includes a biconcave lens coupled to a convex meniscus lens as lens group G50, a fifth doublet includes a convex meniscus lens coupled to a biconvex lens as lens group G60, and a sixth doublet includes a biconvex lens coupled to a concave meniscus lens as lens group G70. The modular approach, extra lens group, and high etendue are each advantageous features of a finite conjugate optical assembly and camera in accordance with several embodiments described herein that are not found in the less capable system illustrated at FIGS. 4A-4C.

[0129] A core zoom module m2 of FIG. 27A, or module m224, module m225 or module m226 of FIGS. 24A-24C, 25A-25C or 26A-26C, respectively, of an example finite conjugate optical assembly, may be configured in accordance with the examples illustrated schematically at FIGS. 5A-11C, 24A-26C, 27A and/or 27E, and may be configured in accordance with one or a combination of the example optical prescriptions shown in Tables 1-7 and 20-22. A core zoom module m2 in accordance with several example embodiments described herein includes five lens groups, while the zoom optical assembly illustrated at FIGS. 4A-4C includes only four groups.

[0130] FIGS. 27A-27G schematically illustrate an embodiment of a modular camera system that includes a lens attachment module m1 in the camera system of FIG. 27A, while examples of lens attachment modules m127, m128, m129, m130, m131, m132 and m133 are provided at FIG. 27G. A core zoom module m2 and a rear adapter module m3 are also included in the camera system of FIG. 27A, while examples of core zoom modules m227, m228, m229, m230, m231 are provided at FIG. 27E and examples of rear adapter modules m327, m328, m329 and m330 are provided at FIG. 27C. The camera system of FIG. 27A also includes a camera mount cm, and FIG. 27B includes examples of camera mounts cm1, cm2 and cm3. FIGS. 27A and 27D include flat mount fm1 and split clamp sc1 components for coupling the complete lens system such as the optical assemblies illustrated schematically in FIGS. 24A-24C to an external fixture. The camera system of FIG. 27A also includes a lighting component lc, while FIG. 27F includes examples of lighting component options LED lc1 and coax lc2, and includes a schematic illustration of a coupler cc for facilitating coupling of a lens attachment module m1 at an object end of a zoom module m2. Multiple further example embodiments are provided for the lens attachment module m1, core zoom module m2, and rear adapter module m3, and are described with reference to FIGS. 5A-26C and Tables 1-25. A modular design in accordance with alternative embodiments may contain two or more modules or modular components that may be conveniently individually isolated for repair or replacement or calibration separate from one or more other modules. A sensor module may be included in an imaging system in accordance with certain embodiments. Other module configurations may include a motorization module, a lighting module, a processing module, an interface module, a communication module or combinations of these.

[0131] In certain embodiments, pupil aberrations are controlled more greatly than in other embodiments, thus advantageously allowing the modularity of the system to function optimally. Optical assemblies in accordance with certain embodiments will have a system magnification greater than 2× at their high magnification point.

[0132] Further example embodiments for afocal zoom lens groups of core zoom module m2 of FIGS. 27A and 27E may include or otherwise be configured in accordance with one or more of the following features. Afocal zoom lenses are provided in accordance with certain embodiments that are configured such as to compress the pupil to a low total movement compared with conventional designs. Optical aberrations may be tightly controlled in these embodiments. These together allow better integration of a multitude of objective lenses and tube lenses that provide optimal performance along with the core zoom. This improved total system performance allows for larger apertures and fields of view than previously available. Combined together this leads to more optical bandwidth, represented by an etendue value at the maximum etendue point which is at the low magnification zoom position at the exit pupil of 0.95 to 4.65 mm²sr for optical systems configured in accordance with certain embodiments for use with 6.6 MP to 32 MP sensors, respectively.

[0133] A first example embodiment of a core zoom module that includes an afocal zoom lens assembly and exhibits a 7:1 ratio of highest to lowest magnification, and an approximate etendue of 1.57 mm²sr at its low magnification position. This embodiment is illustrated schematically at FIGS. 5A-5C, and includes a positive group (G201), a movable negative group (G301), a movable positive group (G401), a movable negative group (G501), and a positive group (G601). A numerical example in accordance with this embodiment is provided in Table 1. Three arrangements are included in FIG. 5A-5C, including a low magnification arrangement at FIG. 5A, a mid-level magnification arrangement at FIG. 5B, and a high magnification arrangement at FIG. 5C.

[0134] The example lens group G201 in FIGS. 5A-5C includes two lens elements including three lenses. The lens group G201 includes a doublet and a singlet, wherein the doublet includes a biconvex lens coupled to a concave meniscus lens, and wherein the singlet includes a convex meniscus lens.

[0135] The example movable lens group G301 in FIGS. 5A-5C includes one lens element including two lenses. The lens group G301 includes a doublet, wherein the doublet includes a biconcave lens coupled to a convex meniscus lens. The movable lens group G301 is disposed a greater distance from lens group G201 in FIG. 5B compared with FIG. 5A, and lens group G301 is disposed closer to lens group G401 in FIG. 5B compared with FIG. 5A. The movable lens group G301 is disposed a greater distance from lens group G201 in FIG. 5C compared with FIG. 5B, and lens group G301 is disposed closer to lens group G401 in FIG. 5C compared with FIG. 5B.

[0136] The movable lens group G401 includes three lens elements including three lenses. The lens group G401 includes a convex meniscus singlet, a biconvex singlet and a concave meniscus singlet. The movable lens group G401 is disposed furthest from lens group G301 and closest to lens group G501 is FIG. 5A, compared with FIGS. 5B-5C, and lens group G401 is disposed closest to lens group G301 and furthest form lens group G501 in FIG. 5C compared with FIGS. 5A-5B.