Abstract: A rod lens is used for fitting in an endoscopes. The rod lens has a rod-shaped body which is made at least in a section of a flexible, transparent solid piece of plastic material.

Abstract: An optical module includes a lens-containing optically-transmissive member and a receptacle. The receptacle includes: an optical connector-inserting section; a fixing section for fixing the member; and an device-installing section for installing a semiconductor device serving as a light emitting device or a light receiving device. The fixing section communicates with the device-installing section. The member includes a main body and a lens. The main body includes a first section and a second section, the first section having a first outer diameter, which is substantially equal to a internal diameter of said fixing section, and said second section having a second outer diameter, which is smaller than the first outer diameter, and at least containing an end of said main body in a side of the device-installing section.

Abstract: A connector defining a receiving opening for receiving a corresponding plug, includes an insulative housing, a plurality of contacts attached to the insulative housing, and a grounding tab. The contacts include a pair of differential signal contacts. Each differential signal contact has a first retaining portion retained in the insulative housing, a first contact portion extending to the receiving opening for contacting with the corresponding plug and a first tail portion for connecting with a circuit board. The first tail portions of the differential signal contacts define a distance which is larger than that of the corresponding first contact portions. The grounding tab is retained between the first tail portions of the pair of differential signal contacts.

Abstract: In one example, a header assembly for use in a communication device has a base that includes a plurality of single ports through which a corresponding plurality of leads extends. The leads are retained in their respective single ports by a retainer material. Additionally, the base includes one or more plural ports through which two or more leads extend.

Abstract: An electronic system includes a first circuit board having a first optical element and a second circuit board having a second optical element positioned to electronically communicate with the first optical element over free space. The system also includes a cold plate having openings positioned to enable the optical communications over free space is positioned between the first circuit board and the second circuit board. The system further includes a condenser and a fluid conduit containing a cooling fluid configured to absorb heat through the cold plate and to convey the heat to the condenser, where the fluid conduit connects the cold plate and the condenser.

Abstract: A plastic housing is arranged on a carrier element and is provided with a recess in which an optoelectronic component is arranged. On the side facing away from the carrier element, the recess has an opening to the outside which can be provided with a transparent cover. One or more structures can be provided on the plastic housing in order to orient the cover and/or optical components relative to the optoelectronic component.

Abstract: An optical module with a sleeve assembly is disclosed. The sleeve assembly, which receives a ferrule secured in an end of the optical connector and is primarily made of resin material, provides a buried member made of a material, typically meal, having a polygonal cross section, a linear thermal expansion coefficient less than that of the resin material and a Young's Modulus greater than that of the resin material. The bore of the sleeve assembly has a deformed circular shape with a first diameter less than the outer diameter of the ferrule.

Abstract: A connector having a chamber (101) for insertion of a plug includes an optical module (4) having lenses (45) exposed to the chamber for transmitting optical data; and an insulative housing having a receiving slot (115) located behind the chamber (101) and communicating with the chamber for receiving the optical module (4), and a top wall (111) for covering the receiving slot (115). The top wall has a set of openings passing therethrough for exposing key side edges of the receiving slot to exterior.

Abstract: An optical element including a transmitting surface section and at least one reflective surface section integrally formed on a main body of the optical element. The transmitting surface section refracts incident light emitted from a predetermined light-emitting position and transmits the light. The reflective surface section reflects the incident light emitted from the light-emitting position such that the light returns to a position differing from the light-emitting position. An optical axis of the transmitting surface section and an optical axis of the reflective surface section are out of alignment such as to be mutually parallel or mutually tilted.

Abstract: An optoelectronic module for converting and coupling an information-containing electrical signal with an optical fiber including a housing having an electrical input for coupling with an external cable or information system device and for transmitting and receiving information-containing electrical signals over such input, and a fiber optic connector adapted for coupling with an external optical fiber for transmitting and receiving an optical signal; an electro-optic subassembly coupled to the information containing electrical signal and converting it to and/or from a modulated optical signal corresponding to the electrical signal; parametric data-collection means disposed in the housing acquiring environmental and/or operational data associated with the module; and a communication interface for wirelessly transferring the data to an external device, such as a portable terminal.

Abstract: An optical communication module includes a CAN member including a conductive stem member where an optical electronic device is mounted and a conducive lens cap that holds an optical lens optically coupled with the optical electronic device, is connected to the stem member in a conductive state, and covers a surrounding portion of the optical electronic device; a conductive cylindrical holder which is disposed around the lens cap, is fixed to the CAN member in an insulation state through an insulating resin, and is provided with an opening facing the optical lens; and an optical receptacle including an optical member that is optically coupled with the optical lens and the optical electronic device through the opening and a holding frame that holds the optical member inside.

Abstract: Fiber optic cable jacks and plugs are provided. In one aspect, a cable is made from at least one length of fiber optic line having a first end and a second end. A first plug includes a one-piece mechanical body with a cable interface to engage the fiber optic line first end, and a microlens to transceive light with the cable interface. The first plug is shaped to engage a first jack housing. A second plug includes a one-piece mechanical body with a cable interface to engage the fiber optic line second end, and a microlens to transceive light with the cable interface. The second plug is shaped to engage a second jack housing. The mechanical bodies have inner walls that form an air gap cavity interposed between the microlens convex surface and an engaging jack optical interface.

Abstract: An optical transmitter module and method for making the module utilizes a housing structure having an integrated lens. The housing structure includes an output opening, which has a central axis along a first direction, to receive an optical fiber. The optical transmitter module further comprises conductive pins that are attached to the housing structure such that the conductive pins extend from the housing structure in a second direction, which is substantially perpendicular to the first direction. The optical transmitter module further comprises a light source mounted on one of the conductive pins such that light from the light source is emitted along the first direction toward the integrated lens of the housing structure to transmit the light into the optical fiber.

Abstract: An optoelectronic module for converting and coupling an information-containing electrical signal with an optical fiber including a housing having an electrical input for detachably coupling with an external cable or information system device and for transmitting and receiving information-containing electrical signals over such input, and a fiber optic connector adapted for coupling with an external optical fiber for transmitting and receiving an optical signal; an electro-optic subassembly coupled to the information containing electrical signal and converting it to and/or from a modulated optical signal corresponding to the electrical signal; a memory disposed in said housing for storing an encrypted identifier; and a communication interface disposed in said housing for electrically transferring the data to an external device when the module is authenticated using the encrypted identifier, to enable operation of the module.

Abstract: Circuits, apparatus, and methods that provide a connector system that can supply both power and data to a mobile computing or other type of device using a single connection. Further examples also provide a power and data adapter that can provide power and data to a mobile computing device using a single cable. Further examples provide an easy disengagement when a cable connected to the connector is pulled. One such example provides a magnetic connector that uncouples without binding when its cord is pulled. Another example prevents power from being provided at a connector insert until the connector insert is placed in a connector receptacle.

Abstract: Electromagnetic radiation (EMR) containment assemblies for use in optoelectronic modules. In one example embodiment, an EMR containment assembly includes an EMR shield and a mounting spring plate attached to the EMR shield. The EMR shield includes a first substantially flat body defining at least one edge, a plurality of optical ports defined in the first body; and a plurality of fingers defined along at least one edge of the first body. The fingers are configured to bias against a housing of an optoelectronic module. The mounting spring plate includes a second substantially flat body defining at least one edge, an optical window defined in the second body, and a plurality of leaf springs defined along at least one edge of the second body. The leaf springs are configured to bias against an alignment guide positioned within the optoelectronic module.

Abstract: A connector (100) includes an insulative housing (1) having a receiving slot (121) formed therein and a post (1221) protruding forwardly towards the receiving slot (121); a set of contacts (2) retained in the insulative housing; an optical module (3) for transmitting optical data and being movably received in the receiving slot along a front-to-back direction; and a compression coil spring (4) sandwiched between the insulative housing and the optical module, and having a front end for biasing the optical module (3) forwardly and a rear end for being retained on the post (1221).

Abstract: The optical module includes an optical device mounting substrate 1 and an optical multiplexer/demultiplexer 2. One laser diode and at least one photodetector, which are positioned in the same plane, are mounted on the optical device mounting substrate 1. The optical multiplexer/demultiplexer is prepared by mounting a wavelength-selective filter and a mirror on the front and back surfaces of a transparent substrate. The optical device mounting substrate and the optical multiplexer/demultiplexer are mounted in a package 3 in such a manner that the optical device mounting surface and the filter surface are not parallel to each other. The optical module also includes a first lens, which is positioned near the laser diode or monolithically integrated with the laser diode, and a second lens, which converges light coming out of the optical multiplexer/demultiplexer toward an optical fiber.

Abstract: A compact optical transceiver is provided in which a substrate provides for an alignment surface for optical fibers and a lens assembly provides the necessary optical paths for coupling to photodiode and photodetector structures. Appropriate electrical connections on the substrate enable the substrate to be directly connected to a printed circuit board, grid array socket, and the like.

Abstract: Systems and methods for controlling the modulation current of a laser included as a component of an optical transmitter, such as an optical transceiver module, are disclosed. Control of the modulation current, which affects various laser operational parameters, including extinction ratio and optical modulation amplitude, enables operation of the laser to be optimized, thereby enabling reliable transceiver performance to be achieved. In one embodiment, a method for modifying the modulation current in an optical transceiver module includes first sensing analog voltage data that proportionally relates to an actual modulation current of the laser. Once sensed, the analog voltage data are converted to digital voltage data. Using the digital voltage data, the actual modulation current of the laser is determined, then a desired modulation current is determined. Should a discrepancy exist between the actual and desired modulation currents, the actual modulation current is modified to match the desired current.

Abstract: The invention relates to a data transmission cable (10; 20), in particular for motor vehicles, at at least one of whose ends a plastics housing (14; 24) is arranged, said housing having mechanical dimensions in its interface region (30; 32) which conform to the FAKRA standardisation scheme. The data transmission cable (10; 20) has an optical waveguide, wherein a holding member (40) is provided in the plastics housing (14; 24), said holding member being configured for holding an optical imaging element (42) and for connecting the optical imaging element (42) to the optical waveguide.

Abstract: Embodiments of the invention include a fiber connector module and method for coupling optical signals between an optical transceiver module and an optical fiber described herein involve the coupling to or overmolding of a fiber connector module to an optical transceiver module or other optical source, and a fiber lens coupled to for formed into an angled surface of the fiber connector module housing. The angled surface and the fiber lens are configured in such a way that the fiber lens focuses collimated light from the transceiver module to the receiving end of an optical fiber or other optical detector positioned within the fiber connector module housing. Fiber connector modules according to embodiments of the invention allow for relatively low profiles compared to conventional arrangements and configurations, especially with multi-channel, parallel lane configurations.

Abstract: This disclosure concerns transceivers that include CDR bypass functionality. In one example, a 10 G XFP transceiver module includes integrated CDR functionality for reducing jitter. The 10 G XFP transceiver module also implements CDR bypass functionality so that the CDR can be bypassed at rate less than about 10 Gb/s, such as the Fibre Channel 8.5 Gb/s rate for example.

Abstract: An optical based input touch display device with high resolution shadow detection using the linear splitting of waveguides among transmit and receive lenses and grey-scale calculations for shadow edge and center detection is disclosed. The apparatus includes a light source and a transmit waveguide optically coupled to the light source. The transmit waveguide includes a plurality of transmit waveguide grooves coupled to a plurality of groups of shared transmit lenses respectively. The plurality of groups of transit lenses, which are configured to generate a plurality of collimated light beams from the light source. A receive waveguide is also provided having a plurality of receive waveguide grooves coupled to a plurality of groups of shared receive lenses. The plurality of groups of receive lenses are configured to receive the plurality of collimated light beams. A photodiode array including a plurality of photodiodes are optically coupled to the plurality of receive waveguide grooves respectively.

Abstract: An optical module is formed by sticking the optical element mounting substrate and the sealing substrate together, then by sealing the stuck body. The optical mounting substrate includes an optical element on its top surface and it is used to guide electrical signals to its back side through a through-via hole provided in itself. The sealing substrate includes a lens at its back side and a recessed part used to hold an optical fiber at its front side.

Abstract: A device comprising: an optical subassembly has a lens rear surface including one or more facets for scattering at least some of the light transmitted through the lens rear surface.

Abstract: Embodiments of the present invention are directed to a dual stage modular optical device for sending and/or receiving optical signals. A first fabricated package includes a light source for generating optical signals and/or a light detector for detecting received optical signals. A second fabricated package includes an opening for accepting circuitry that is to electrically interoperate with the light source and/or light detector to transfer optical signals. A lead frame mechanically connects the first fabricated package to the second fabricated package and electrically connects the light source and/or light detector to contacts exposed in the opening. The dual stage modular optical device can be coupled to a substrate configured to be received within a standard slot of a host system, such as a PCI or PCMCIA slot. Thus, one or more optical connections are integrated within the host device or system.

Abstract: An optical module includes a receptacle for receiving an optical connector attached to a distal end of an optical fiber, and a lens body having a contact surface coming into contact with the distal end of the optical fiber when the receptacle receives the optical connector. The lens body has the contact surface and an opposing surface opposing the contact surface, and further has a columnar base held by the receptacle, a lens portion formed on the opposing surface integrally with the base, and a flat portion. The lens portion is surrounded by the flat portion and is off-centered with respect to the base.

Abstract: A connector (100) includes an insulative housing (1) having a base portion (11), a first tongue portion (12) extending forwardly from the base portion and a plurality of first passageways (123), the first tongue portion is thinner than the base portion and defines a front mating face (120), an upper side face (121) and a lower side face (122) opposite to the upper side face. A number of first electrical contacts (21) are received in the first passageways respectively, the first electrical contacts each defines a first contacting portion (210), a first soldering portion (212) and a first retaining portion (211) connecting with the first contacting portion and the first soldering portion. A number of optical components (4, 5) are mounted on the first tongue portion and exposed to exterior through the front mating face.

Abstract: An optical link module, includes: a lead frame including at least two notches at an outer edge of its major surface; a substrate bonded to the major surface of the lead frame so that the notches are exposed therearound; an optical element having an optical axis generally perpendicular to the major surface and bonded onto the substrate using the notches as a positioning reference; and a receptacle housing being in contact with the lead frame to cover the substrate and the optical element, and including a tubular ferrule guide portion having a central axis generally in alignment with the optical axis and guide pins fitted into the notches.

Abstract: A beam coupler assembly for a fiber laser is disclosed. The assembly includes a housing having a sidewall with an interior surface, an exterior surface, a first end and a second end. A first seal extending from the interior surface of the tubular housing and dividing the housing into a first section and a second section is also provided. The first section and second section are environmentally isolated from one another. However, the first seal is substantially optically neutral. An input collimator unit received within the first end of the sidewall of the housing and into the first section and is releasably coupled thereto. An output collimator unit received within the second end of the sidewall of the housing and into the second section and is also releasably coupled thereto.

Abstract: An optical receptacle (100) includes an insulative housing (1), a pair of power contacts (2) and an optical fiber component (3) retained in the insulative housing (1). The insulative housing (1) have a body portion (11), a tongue portion (12) extending forwardly from the body portion (11), a pair of passageways (123) extending through insulative housing (1), and a receiving cavity (114) below the passageways (123). The body portion (11) has a pair of opposed front face (110) and rear face (111), and a pair of opposed upper face (112) and lower face (113). Each power contacts (2) has a contacting portion (21), a soldering portion (23) and a retaining portion (22) connecting with the contacting portion (21) and the soldering portion (23. The optical fiber component (3) is retained in the receiving cavity (114) and being exposed to exterior through the front face (110).

Abstract: An integrated optical interconnect. The integrated optical interconnect includes a receptacle for connecting to a first external component. The receptacle includes an EMI shield with an aperture sized to allow transmission of an optical signal through the aperture while containing EMI within the receptacle. The integrated optical interconnect also includes a port injection molded around or within a portion of the receptacle, the port being configured to receive a second external component and a lens injection molded near a location of the aperture of the EMI shield.

Abstract: Consistent with the present disclosure, a package is provided in which the PLC substrate, for example, is bonded to the underyling carrier though a limited contact area. The rest of the substrate is detached from the carrier so that stresses are applied to a limited portion of the PLC substrate. The PLC itself, however, is provided over that portion of the substrate that is detached from the carrier, and thus experiences reduced stress. Accordingly, high modulus adhesives, as well as solders, may be used to bond the PLC substrate to the carrier, thereby resulting in a more robust mechanical structure.

Abstract: Modules and signal control circuits configured to at least partially compensate for or adjust for asymmetric rise/fall time. The circuit may include a first input node configured to receive a first data signal and a second input node configured to receive a second data signal that is complementary of the first data signal. The circuit may also include a first stage having a first node coupled to the first input node and a second node coupled to the second input node and a second stage having a first node coupled to a third node of the first stage and a second node coupled to a fourth node of the first stage. The second stage may be configured to drive a load such as a laser. The circuit may further include a third input node configured to receive a third data signal and a fourth input node configured to receive a fourth data signal that is the complementary of the third data signal.

Abstract: A bi-directional optical subassembly (BOSA) with a unique arrangement to set the WDM filter is disclosed. The BOSA includes the stem and the lens cap. The stem mounts both the LD and the PD. While, the lens cap provides, in addition to the condenser lens, a structure to set the WDM filter in a top center thereof. The WDM filter is set in the lens cap with a present angle to the primary surface of the stem when the lens cap is fixed to the stem. Assembling the lens cap with the stem, the relative optical alignment between the LD, the PD and the WDM filter is performed.

Abstract: Methods and systems for using a wavelength as an address in an optical network are disclosed. In particular, methods for selecting a wavelength for a particular node in an optical network, resolving a wavelength for a destination node in an optical network from a network address, and receiving and transmitting data packets at particular wavelengths are disclosed. A resulting system implementing such methods may significantly reduce space, weight and power measurements while transferring data at high rates for a data network.

Abstract: A coaxial opto-electronic device used for SFF (Small Form Factor) and SFP (Small Form-Factor pluggable) opto-electronic transceiver module comprises an opto-electronic TO CAN (201) having a cap border (106) at one end, a metal tube (203) disposed around the opto-electronic TO CAN (201), and an isolation ring (202) interposed between the end face of the metal tube (203) and the cap border (106). The coaxial opto-electronic device allows the device's metal case ground to be insulated from the inner data ground, and at the same time, the device outer form is small enough and the size of inner part thereof is enlarged.

Abstract: Double mold opto-coupler and method for manufacture. A first subassembly is formed that includes a light detector. The first subassembly is molded with a first mold material to form a molded first subassembly. A light source is attached to the molded first sub-assembly to form a second sub-assembly. The second sub-assembly is molded with a second mold material to form a final assembly with predetermined dimensions.

Abstract: An optoelectronic surface-mounted device is provided comprising a premolded casing having a first cavity and a second cavity and a leadframe to which a first electrooptical element and a second electrooptical element are mounted. The leadframe is embedded in the premolded casing. The first cavity is adapted for providing a first electromagnetic radiation path between a first waveguide and the first electrooptical element, wherein the second cavity is adapted for providing a second electromagnetic radiation path between a second waveguide and the second electrooptical element. The first cavity and the second cavity are formed in the premolded casing to decouple electromagnetic radiation propagating along the first electromagnetic radiation path from electromagnetic radiation propagating along the second electromagnetic radiation path.

Abstract: The invention is relevant to optical fiber transmission systems, and in particular, pertains to the transceiver cards in an optical fiber transport system. In particular the invention teaches an improved transceiver card architecture that allows high density, flexibility and interchangeability of functionality.

Abstract: A first toroidal ray guide defines an axis of revolution and has a toroidal entrance pupil adapted to image light incident on the entrance pupil at an angle to the axis of revolution between 40 and 140 degrees, and it also has a first imaging surface opposite the entrance pupil. A second toroidal ray guide also defines the same axis of revolution and has a second imaging surface adjacent to the first imaging surface. Various additions and further qualities of the ray guides, which form optical channels, are disclosed. In a method light emanating from a source at between 40-140 degrees from an optical axis is received at an entrance pupil of a ray guide arrangement that is circularly symmetric about the optical axis. Then the received light is redirected through the ray guide arrangement to an exit pupil in an average direction substantially parallel to the optical axis.

Abstract: An optical module includes a fiber array, a laser diode array, a photodiode array and a micro-lens array. The fiber array includes optical fibers which are divided to a transmitter group and a receiver group. The laser diode array includes laser diodes which are grouped in a transmitter group. The photodiode array includes photodiodes which are divided to a monitor group and a receiver group. The laser diode array is provided between the fiber array and the photodiode array. The optical fibers of the transmitter group are optically aligned with the laser diodes of the transmitter group, respectively. The micro-lens array is provided between the laser diode array and the photodiode array, and optically aligns the laser diodes of the transmitter group and the optical fibers of the receiver group with the photodiodes of the monitor group and the photodiodes of the receiver group, respectively.

Abstract: In general, in one aspect, a method includes forming conductive layers on a wafer. A through cavity is formed in alignment with the conductive layers. The through cavity is to permit an optical signal from an optical waveguide within an optical connector to pass therethrough. Alignment holes are formed on each side of the through cavity to receive alignment pins. The wafer having the conductive layers, the through cavity in alignment with the conductive layers, and the alignment holes on each side of the through cavity forms an optical-electrical (O/E) interface. An O/E converter is mounted to the metal layers in alignment with the through cavity. The alignment pins and the alignment holes are used to passively align the optical waveguide and the O/E converter.

Abstract: An optical fiber connector (100) includes a first insulative housing (1), a door (2) assembled in the first housing and an elastic piece (3) with one end retained in the first housing and the other end elastically abutting against the door. The first housing defines a top face (10), a front face (11) connecting with the top face and a pair of sidewalls (13). The first housing further defines a receiving cavity (111) opening through the front face thereof, and each sidewall defines a recess (112) opening through the top face and the inner surface of the receiving cavity near an opening of the receiving cavity. The door is movably assembled at the opening of the receiving cavity and defines a pair of shafts (22) received in the recesses. Each recess integrally defines a protrusion (113) over the shaft therein, so as to prevent the shafts from breaking off the recesses.

Abstract: An optical connector (1) includes an housing (2) having a front wall, an upper wall, a bottom wall, a pair of side walls and a receiving cavity (215) formed therebetween for receiving a mating plug; and an optical member (3) having an optical portion (31) for receiving or emitting light and a number of contacts connected to the optical portion; an insulative cover member (25) attached to the housing and defining a first portion (251) covering an upper portion of the housing and a second portion (258) enclosing a rear portion of the housing, the first portion defining a cutout (252) extending therethrough along an up-to-down direction; a metal lock member (6) defining a lateral arm (61) being retained in the cutout and a locking portion (62) extending downward from the lateral arm and projecting through the housing to be soldered to a printed circuit board, the locking portion locks with the housing.

Abstract: An electro-optical assembly (EA) is provided in which the transmitter and receiver components are integrated together on a single circuit board, which is encapsulated in a single molded EA package. Integrating the transmitter and receiver components on a single circuit board allows the size and complexity of the EA to be greatly reduced as compared to the traditional TO-can and FOT architectures. A standard semiconductor inline automation system and process may be used to manufacture the EA packages so that they may be mass produced with improved throughput, yield and quality as compared to the method currently used to manufacture and assemble the known EA used in the traditional TO-can and FOT architectures.

Abstract: When operation keys are operated, a light-emitting device outputs an infrared signal corresponding to the operated operation keys. The infrared signal is applied to a light-detecting device. In response to the applied infrared signal, the light-detecting device generates a detected signal and supplies the detected signal to an amplifying circuit. The amplified detected signal from the amplifying circuit is decoded by a decoding circuit into a data code, which is supplied through an interface circuit to a computer. Based on control data supplied as the data code to the computer, the computer controls a projector to perform a process of displaying images page by page, for example.

Abstract: A plastic optical fiber connector includes an optical fiber connector having a plate body formed therein. On the plate body, a focusing hole is formed, the focusing hole having a holding portion extending outwardly from a side thereof. With provision of the plate body, two reception spaces are formed in the optical fiber connector, with one of which having a seat body on which an optical transceiver is provided therein, wherein a transceiver terminal of the optical transceiver is bonded to the focusing hole on the plate body. Further, a wire seat is sleeved within the optical fiber connector so that the holding portion is allowed to be placed into an optical fiber guiding hole of the wire seat.

Abstract: A method and apparatus for maintaining an alignment of a laser diode with an optical fiber is disclosed. A mounting plate is made of a first material, and mounted on the mounting plate is a first substrate made of a second material. A semiconductor laser, with a light emitting side, is mounted on the first substrate. Separated from the first substrate by a predetermined distance is a second substrate made of a third material, and mounted on the second substrate is an optical fiber. The optical fiber is mounted, such that, the optical fiber is adjacent to and aligned with the light emitting side of the semiconductor laser. The first, second, and third materials making up the mounting plate, the first substrate, and the second substrate respectively, facilitate maintenance of the alignment between the optical fiber and the light emitting side of the semiconductor laser.