Optical communication module with lens unit having extension portions mounted on circuit board

[0001] 1. Technical Field

[0002] The present disclosure relates to optical communication modules and, particularly, to an optical communication module having good binding force.

[0003] 2. Description of Related Art

[0004] Optical communication modules comprise circuit boards, laser diodes, photo diodes, and lens units, for example. In package of the optical communication modules, the laser diodes and photo diodes are located on the circuit board first, and then glue is coated on the circuit board, and the lens unit is fixed on the glue to combine with the laser diodes and the photo diodes.

[0005] However, the glue is only coated between the bottom of the lens unit and the circuit board, so not only that the contact size between the lens unit and the circuit board is small but also that the binding force of the lens unit and the circuit board is small. When the circuit board fixed with the lens unit is connected with other structures, the lens unit may be detached from the circuit board.

[0006] Therefore, it is desirable to provide an optical communication module, which can overcome the limitations described.

[0011] FIGS. 1 to 3 show an optical communication module 100 of an embodiment. The optical communication module 100 comprises a lens unit 10 and an optical-electrical converter 20.

[0012] The optical-electrical converter 20 comprises a circuit board 21 and optical-electrical components 22 for receiving and emitting light. The optical-electrical components 22 comprise light emitting diodes for emitting light, and photo diodes for receiving light. The circuit board 21 can be hard circuit boards or flexible circuit boards. When the circuit board 21 is a hard circuit board, the material of the circuit board 21 may be ceramic.

[0013] The lens unit 10 comprises a first surface 111, a second surface 112, a third surface 113, and a fourth surface 114 joined end to end in turn. The first surface 111 faces the third surface 113 and the second surface 112 faces the fourth surface 114. The lens unit 10 is fixed on the circuit board 21. The first surface 111, the second surface 112, the third surface 113, and the fourth surface 114 is perpendicularly fixed onto the circuit board 21 respectively.

[0014] The first surface 111 extends to form a first extension portion 11a and the third surface 113 extends to form a second extension portion 11b, the second surface 112 extends to form a third extension portion 12a, and the fourth surface 114 extends to form a fourth extension portion 12b. The first extension portion 11a, the second extension portion 11b, the third extension portion 12a, and the fourth extension portion 12b respectively are parallel with the circuit board 21.

[0015] In other embodiments, the lens unit 10 can only comprise the first extension portion 11a and the second extension portion 11b, or the lens unit 10 can only comprises the third extension portion 12a and the fourth extension portion 12b. In other words, the first surface 111 and the second surface 112 have extension portions or the third surface 113 and the fourth surface 114 have extension portions.

[0016] The lens unit 10 also comprises a fifth surface 115 and a sixth surface 116. The fifth surface 115 faces away from the circuit board 21. The sixth surface 116 faces toward the circuit board 21. A plurality of first lenses 117 are formed on the first surface 111. A plurality of second lenses 118 are formed on the sixth surface 116 respectively. The number of the first lenses 117 is identical to the number of the second lenses 118. The optical axes of the first lenses 117 are parallel with each other. The optical axes of the second lenses 118 are parallel with each other. A reflecting surface 119 is set between the fifth surface 115 and the sixth surface 116. The reflecting surface 119 is inclined to the fifth surface 115 and the sixth surface 116. The reflecting surface 119 is configured for reflecting the light passing through the first lenses 117 and the second lenses 118. Each of the first lenses 117 is coupled with an optical fiber. Light beams passing through the optical fiber irradiate on the reflecting surface 119 through the first lens 117. After being reflected by the reflecting surface 119, the light beams pass through the second lens 118. At last, the photo diodes of the optical-electrical components 22 located on the circuit board 21 receive the light beams respectively. The light beams emitted by the light emitting diodes of the optical-electrical components 22 pass through the second lenses 118 and the reflecting surface 119 in turn, and then are coupled into the optical fibers by the first lenses 117 respectively.

[0017] Both an included angle between the reflecting surface 119 and the optical axis of the first lens 117 and an included angle between the optical axis of the second lens 118 and the reflecting surface 119 are 45 degrees. An included angle between the circuit board 21 and the reflecting surface 119 is also 45 degrees.

[0018] In assembly, glue 30 is coated on the circuit board 21, and the lens unit 10 is mounted on the glue 30, with each of the first extension portion 11a, the second extension portion 11b, the third extension portion 12a, and the fourth extension portion 12b mounted on the circuit board 21 through the glue 30. The glue 30 is solidified, the lens unit 10 is fixed on the circuit board 21.

[0019] The first extension portion 11a, the second extension portion 11b, the third extension portion 12a, and the fourth extension portion 12b increase the contact area between the lens unit 10 and the circuit board 21. When the lens unit 10 is fixed on the circuit board 21, the glue 30 is coated not only between the bottom of the lens unit 10 and the circuit board 21, but also between each of the extension portions 11a, 11b, 12a, 12b and the circuit board 21. Thus, a binding force between the lens unit 10 and the circuit board 21 increases.

[0020] It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its material advantages, the examples hereinbefore described merely being exemplary embodiments of the disclosure.