# US 5,705,833 A · Surface-mounted photocoupler > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,705,833 A - Document ID: US5705833A - Status: Granted - Kind: A - Application number: 08/575,837 - Filed: 1995-12-20 - Granted: 1998-01-06 - Earliest claimed: 1994-12-30 - Assignees: Citizen Electronics Co., Ltd. - Inventors: Katsuhiko Noguchi; Megumi Horiuchi - Web page: https://patentgrep.com/patent/US5705833A ## CPC - H10F 55/255: formed in, or on, a common substrate - H10W 72/536: {the connected ends being ball-shaped} - H10W 72/5363: {the connected ends being wedge-shaped} - H10W 90/756: {between a chip and a stacked lead frame, conducting package substrate or heat sink} - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A light-emitting element 22 and a light-receiving element 26 are attached to a circuit board so as to oppose each other across the circuit board 2. As a result, light from the light-emitting element 22 arrives at the light-receiving element 26 via the substrate 2. Since the distance between the light-emitting element 22 and the light-receiving element 23 thus becomes very short, the light conversion efficiency is improved by a wide margin. Further, since the substrate 2 is interposed between the light-emitting element 22 and the light-receiving element 26, the elements are completely isolated within the insulation breakdown voltage of the material constituting the substrate. ## Claims ### Claim 1 A surface-mounted photocoupler comprising; a light-transparent substrate including a mounting portion one side of which is projected to form a protrusion and the opposite side of which forms a recess; first and second electrode patterns formed on one and other surfaces of said mounting portion, respectively; a light-emitting element attached to said one surface of said mounting portion and electrically connected to said first electrode patterns; a light-receiving element attached to said other surface of said mounting portion, so as to oppose said light-emitting element across said substrate, and electrically connected to said second electrode patterns; and a synthetic resin covering said light-emitting element and said light-receiving element. ### Claim 2 (depends on 1) A surface-mounted photocoupler according to claim 1, wherein said mounting portion has a horizontal portion, and wherein said light-emitting element and light-receiving element are attached to said horizontal portion. ### Claim 3 (depends on 2) A surface-mounted photocoupler according to claim 2, wherein said mounting portion has a frusto-conical configuration. ### Claim 4 (depends on 2) A surface-mounted photocoupler according to claim 2, wherein said substrate is composed of thermoplastic polyimide film. ### Claim 5 (depends on 1) A surface-mounted photocoupler according to claim 1, wherein said light-emitting element comprises an LED having a rectangular configuration, and wherein said LED has a bottom side fixed to said one surface of said mounting portion, a light-emitting portion formed on said bottom side, side faces and electrodes formed on said side faces and connected to said first electrode patterns. ### Claim 6 (depends on 1, 5) A surface-mounted photocoupler according to claim 1 or 5, wherein said light-receiving element comprises a phototransistor having a rectangular configuration, and wherein said phototransistor has a bottom side fixed to said other surface of said mounting portion and a base, an emitter and a collector formed on the bottom side, said emitter and collector being connected to said second electrode patterns. ### Claim 7 A surface-mounted photocoupler comprising: a light-transparent substrate including a flat mounting portion and edge portions; first and second electrode patterns formed on one and other surfaces of said flat mounting portion, respectively; a light-emitting element attached to said one surface of mounting portion and electrically connected to said first electrode patterns; a light-receiving element attached to said other surface of said mounting portion, so as to oppose said light-emitting element across said substrate, and electrically connected to said second electrode patterns; and a synthetic resin covering said light-emitting element and said light-receiving element and formed in a rectangular configuration; wherein said edge portions are bent and affixed along the outer periphery of said syntectic resin covering one of said light-emitting element and light-receiving element. ### Claim 8 A surface-mounted photocoupler comprising: a light-transparent substrate including a mounting portion one side of which is projected to form a protrusion and the opposite side of which forms a recess and a horizontal portion at the center of said mounting portion; first and second electrode patterns formed on one and other surfaces of said horizontal portion of said mounting portion, respectively; an LED formed in a rectangular configuration and having a bottom side fixed to said one surface of said horizontal portion of said mounting portion, a light-emitting portion formed on said bottom side, side faces and electrodes formed on said side faces and electrically connected to said first electrode patterns; a phototransistor formed in a rectangular configuration and having a bottom side fixed to said other surface of said horizontal portion of said mounting portion, so as to oppose said LED across said horizontal portion, and a base, an emitter and a collector formed on the bottom side, said emitter and collector being electrically connected to said second electrode patterns, and said base facing said light-emitting portion of said LED through said horizontal portion of said mounting portion; and a synthetic resin coveting said LED and said phototransistor.