Abstract: Semiconductor laser assembly 1 is provided with semiconductor laser device 6 and heat dissipation member 24. Semiconductor laser device 6 includes semiconductor laser element 15, lead-frame 11, lower and upper enclosures 18 and 19 and plate-like spring 21 connected to lead-frame 11. Semiconductor laser element 15 is mounted on lead-frame 11 through sub-mounting member 16. Lower and upper enclosures 18 and 19 have an opening through which laser beams from semiconductor laser element 15 are emitted. Plate-like spring 21 is connected to lead-frame 11 and has wing and holding portions 22 and 23. Holding portion 23 is a C-character in cross section to put lower and upper enclosures 18 and 19 together. Heat dissipation member 24 has inside walls to define perforation 25, so that wing portions 22 of plate-like spring 21 pushes semiconductor laser device 6 against the inside walls of heat dissipation member 24 when the semiconductor laser device 6 is set in perforation 25.

Abstract: In one aspect, a semiconductor laser device may include a supporting member, a semiconductor laser element provided over the supporting member, and configured to emit a laser from a front surface and monitoring laser from a rear surface, and a photo receiving element provided over the supporting member, and configured to receive the monitoring laser from the semiconductor laser element at a photo receiving region, the photo receiving region provided on a side surface of the photo receiving element, wherein the side surface of the photo receiving element has a smaller area than an area of a bottom surface of the photo receiving element.

Abstract: A semiconductor laser array is described. The semiconductor laser array may include a plurality of semiconductor laser elements including a first laser element and a second laser element. The first laser element may be configured to emit a shorter wavelength laser than the second laser element. The emission portion of the first laser element provided substantially on a center line of a substrate.

Abstract: One aspect of the present invention may include a semiconductor laser array, comprising: a substrate; a first laser element on the substrate, the first laser element having a first resonator; a second laser element on the substrate, the second laser element having a second resonator, the second resonator being shorter in cavity length than the first resonator; and a protrusion on the substrate, the protrusion being substantially equal in height from the substrate with one of the first laser element and the second laser element.

Abstract: Semiconductor laser assembly 1 is provided with semiconductor laser device 6 and heat dissipation member 24. Semiconductor laser device 6 includes semiconductor laser element 15, lead-frame 11, lower and upper enclosures 18 and 19 and plate-like spring 21 connected to lead-frame 11. Semiconductor laser element 15 is mounted on lead-frame 11 through sub-mounting member 16. Lower and upper enclosures 18 and 19 have an opening through which laser beams from semiconductor laser element 15 are emitted. Plate-like spring 21 is connected to lead-frame 11 and has wing and holding portions 22 and 23. Holding portion 23 is a C-character in cross section to put lower and upper enclosures 18 and 19 together. Heat dissipation member 24 has inside walls to define perforation 25, so that wing portions 22 of plate-like spring 21 pushes semiconductor laser device 6 against the inside walls of heat dissipation member 24 when the semiconductor laser device 6 is set in perforation 25.

Abstract: A signal transmission circuit having a latch-up function has a first and a second photo-couplers, each of which has a photo-diode (light emitting diode) and a photo-transistor. The photo-diode in the first photo-coupler is series-connected with the photo-transistor in the second photo-coupler between high and low voltage supplies. The other photo-diode and photo-transistor in said first and second photo-couplers are connected in the same way. As a result, signals are transmitted between those two photo-couplers with a high noise resistance.