# US 11,444,436 B2 · Semiconductor optical amplifier, semiconductor optical amplification device, optical output device, and distance measuring device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,444,436 B2 - Document ID: US11444436B2 - Status: Granted - Kind: B2 - Application number: 16/804,819 - Filed: 2020-02-28 - Published: 2020-09-03 - Granted: 2022-09-13 - Earliest claimed: 2019-03-01 - Assignees: FUJIFILM Business Innovation Corp. - Applicants: Fujifilm Business Innovation Corp.; Tokyo Institute of Technology - Inventors: Junichiro Hayakawa; Daiki Tominaga; Akemi Murakami; Fumio Koyama - Web page: https://patentgrep.com/patent/US11444436B2 ## CPC - H01S 5/50: Amplifier structures not provided for in groups H01S5/02 - H01S5/30 - H01S 5/5018: {using two or more amplifiers or multiple passes through the same amplifier} - H01S 5/18344: {characterized by the mesa, e.g. dimensions or shape of the mesa} - H01S 5/18361: {Structure of the reflectors, e.g. hybrid mirrors} - H01S 5/0265: {Intensity modulators (intra-cavity modulators H01S5/0625)} - H01S 5/0654: {Single longitudinal mode emission} - H01S 5/1021: {Coupled cavities (H01S5/14 takes precedence)} - H01S 5/1032: {Coupling to elements comprising an optical axis that is not aligned with the optical axis of the active region} - H01S 5/125: Distributed Bragg reflector [DBR] lasers - H01S 5/183: having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL] - H01S 5/18311: {using selective oxidation} - H01S 5/1835: {Non-circular mesa} - H01S 5/18394: {Apertures, e.g. defined by the shape of the upper electrode} - H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL ## Abstract A semiconductor optical amplifier includes: a substrate; a light source unit that is formed on the substrate; and an optical amplification unit that includes a conductive region extending, from the light source unit, in a predetermined direction along a surface of the substrate, and a nonconductive region around the conductive region. The optical amplification unit amplifies propagation light that propagates, from the light source unit, in the predetermined direction as slow light, and emits the propagation light that is amplified in an emission direction that intersects with the surface. The maximum optical power of the propagation light is larger than the maximum optical power in a vertical oscillation mode. ## Claims ### Claim 1 A semiconductor optical amplifier comprising: a substrate; a light source unit that is formed on the substrate; and an optical amplification unit that includes a conductive region extending, from the light source unit, in a predetermined direction along a surface of the substrate, and a nonconductive region around the conductive region, the optical amplification unit amplifying propagation light that propagates, from the light source unit, in the predetermined direction as slow light, the optical amplification unit emitting the propagation light that is amplified in an emission direction that intersects with the surface, wherein maximum optical power of the propagation light is larger than maximum optical power in a vertical oscillation mode. ### Claim 2 (depends on 1) A semiconductor optical amplification device comprising: the semiconductor optical amplifier according to claim 1; and a drive unit that drives the semiconductor optical amplifier with driving current such that optical power in a slow light mode becomes larger than optical power in a vertical oscillation mode. ### Claim 3 (depends on 2) An optical output device comprising: the semiconductor optical amplification device according to claim 2; and a light condensing unit that condenses light emitted from the semiconductor optical amplification device. ### Claim 4 (depends on 2) A distance measuring device comprising: the semiconductor optical amplification device according to claim 2; a light receiving unit that receives light that is emitted from the semiconductor optical amplification device and is reflected from an object to be measured; and a measuring unit that measures the distance to the object based on the light received by the light receiving unit. ### Claim 5 (depends on 2) The semiconductor optical amplification device according to claim 2, further comprising a temperature control unit that controls temperature of the semiconductor optical amplifier such that the optical power in the slow light mode becomes larger than the optical power in the vertical oscillation mode while the semiconductor optical amplifier being driven. ### Claim 6 (depends on 5) An optical output device comprising: the semiconductor optical amplification device according to claim 5; and a light condensing unit that condenses light emitted from the semiconductor optical amplification device. ### Claim 7 (depends on 5) A distance measuring device comprising: the semiconductor optical amplification device according to claim 5; a light receiving unit that receives light that is emitted from the semiconductor optical amplification device and is reflected from an object to be measured; and a measuring unit that measures the distance to the object based on the light received by the light receiving unit. ### Claim 8 (depends on 5) The semiconductor optical amplification device according to claim 5, wherein the temperature control unit controls temperature of the optical amplification unit to prevent oscillation in the vertical oscillation mode. ### Claim 9 (depends on 8) An optical output device comprising: the semiconductor optical amplification device according to claim 8; and a light condensing unit that condenses light emitted from the semiconductor optical amplification device. ### Claim 10 (depends on 8) A distance measuring device comprising: the semiconductor optical amplification device according to claim 8; a light receiving unit that receives light that is emitted from the semiconductor optical amplification device and is reflected from an object to be measured; and a measuring unit that measures the distance to the object based on the light received by the light receiving unit. ### Claim 11 (depends on 1) The semiconductor optical amplifier according to claim 1, wherein oscillation in a vertical oscillation mode is prevented. ### Claim 12 A semiconductor optical amplification device comprising: a substrate; a light source unit that is formed on the substrate; an optical amplification unit that includes a conductive region extending, from the light source unit, in a predetermined direction along a surface of the substrate, and a nonconductive region around the conductive region, the optical amplification unit amplifying propagation light that propagates, from the light source unit, in the predetermined direction as slow light, the optical amplification unit emitting the propagation light that is amplified in an emission direction that intersects with the surface; and a drive unit that drives the optical amplification unit with driving current such that optical power in a slow light mode becomes larger than optical power in a vertical oscillation mode. ### Claim 13 (depends on 12) An optical output device comprising: the semiconductor optical amplification device according to claim 12; and a light condensing unit that condenses light emitted from the semiconductor optical amplification device. ### Claim 14 (depends on 12) A distance measuring device comprising: the semiconductor optical amplification device according to claim 12; a light receiving unit that receives light that is emitted from the semiconductor optical amplification device and is reflected from an object to be measured; and a measuring unit that measures the distance to the object based on the light received by the light receiving unit. ### Claim 15 A semiconductor optical amplification device comprising: a light source unit that is formed on a substrate; an optical amplification unit that includes a conductive region extending, from the light source unit, in a predetermined direction along a surface of the substrate, and a nonconductive region around the conductive region, the optical amplification unit amplifying propagation light that propagates, from the light source unit, in the predetermined direction as slow light, and emitting the propagation light that is amplified in an emission direction that intersects with the surface; and a temperature control unit that controls temperature of the optical amplification unit such that optical power in a slow light mode becomes larger than optical power in a vertical oscillation mode while the optical amplification unit being driven. ### Claim 16 (depends on 15) An optical output device comprising: the semiconductor optical amplification device according to claim 15; and a light condensing unit that condenses light emitted from the semiconductor optical amplification device. ### Claim 17 (depends on 15) A distance measuring device comprising: the semiconductor optical amplification device according to claim 15; a light receiving unit that receives light that is emitted from the semiconductor optical amplification device and is reflected from an object to be measured; and a measuring unit that measures the distance to the object based on the light received by the light receiving unit.