# US 5,710,671 A · Optical system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,710,671 A - Document ID: US5710671A - Status: Granted - Kind: A - Application number: 08/711,322 - Filed: 1996-09-03 - Granted: 1998-01-20 - Earliest claimed: 1995-09-05 - Assignees: Temic Telefunken microelectronic GmbH - Inventors: Gunther Bichlmaier - Web page: https://patentgrep.com/patent/US5710671A ## CPC - G08B 13/181: using active radiation detection systems - B60R 25/1004: {Alarm systems characterised by the type of sensor, e.g. current sensing means (using door lock sensors B60R25/1001)} - G02B 3/08: with discontinuous faces, e.g. Fresnel lens {(diffractive Fresnel lenses G02B5/1876)} - H04B 10/1149: {Arrangements for indoor wireless networking of information} - G08B: SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS - B60R: VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H04B: TRANSMISSION ## Abstract An optical system with an optical unit consisting of a transmission unit with at least one transmission element for emitting optical radiation, a receiving unit with at least one receiving element for detecting optical radiation and an optical path for transmitting the optical radiation between transmission unit and receiving unit. At least one optical unit is located in the optical path to bundle and deflect the optical radiation and an optical body/optical bodies is/are assigned to either the transmission unit or the receiving unit. The optical bodies are designed as a kind of Fresnel lens and have an unstructured surface side and a structured surface side having indentations with steep flanks large slope angle and a small prism angle. The structured surface side of the optical body with indentations forms a first boundary surface for total reflection and a second boundary surface for refracting the optical radiation emitted from the transmission unit or the optical radiation detected by the receiving unit and is turned away from either the transmission unit or the receiving unit. ## Claims ### Claim 1 Optical system with an optical unit comprising: a) a transmission unit with at least one transmission element for emitting optical radiation; b) a receiving unit with at least one receiving element for detecting optical radiation; c) an optical path for transmitting the optical radiation between transmission unit and receiving unit; wherein: d) at least one optical body is located in the optical path to bundle and deflect the optical radiation, with the at least one optical body being assigned either to the transmission unit or the receiving unit; e) the at least one optical body is a type of Fresnel lens having an unstructured surface side, and a structured surface side having indentations, with flanks having a slope angle (.alpha.) and a prism angle (.delta.), arranged in concentric circles, with the indentations having a notch shape with the slope angle (.alpha.) of the flanks of the indentations increasing in a direction from the edge to the center of the at least one optical body, and with the prism angle (.delta.) decreasing in a direction from the edge to the center of the at least one optical body; and, f) the structured surface side of the at least one optical body with indentations provides a first boundary zone for total reflection and a second boundary zone for refraction of the optical radiation emitted from the transmission unit or of the optical radiation to be detected by the receiving unit and is turned away from either the transmission unit or the receiving unit. ### Claim 2 (depends on 1) Optical system in accordance with claim 1, wherein the at least one optical are made in the form of body is a circular disk. ### Claim 3 (depends on 1) Optical system in accordance with claim 1, wherein the slope angle (.alpha.) of the flanks of the indentations is in the range between 40.degree. and 65.degree.. ### Claim 4 Optical system with an optical unit comprising: a) a transmission unit with at least one transmission element for emitting optical radiation; b) a receiving unit with at least one receiving element for detecting optical radiation; c) an optical path for transmitting the optical radiation between the transmission unit and the receiving unit; and wherein: d) at least one optical body is located in the optical path to bundle and deflect the optical radiation, with the at least one optical body being assigned either to the transmission unit or to the receiving unit; e) the at least one optical body is a type of Fresnel lens have an unstructured surface side and a structured surface side having indentations with flanks, a slope angle (.alpha.) for the flanks in the range between 40.degree. and 65.degree., and a prism angle (.delta.)complementary to the slope angle; and, f) the structured surface side of the at least one optical body with indentations provides a first boundary zone for total reflection and a second boundary zone for refraction of the optical radiation emitted from the transmission unit or of the optical radiation to be detected by the receiving unit, and is turned away from either the transmission unit or the receiving unit. ### Claim 5 (depends on 4) Optical system in accordance with claim 4, wherein the indentations are arranged in concentric circles on the structured surface side of the at least one optical body. ### Claim 6 (depends on 5) Optical system in accordance with claim 5, wherein the indentations arranged on the structured surface side of the at least one optical body are of notch shape with a slope angle (.alpha.) of the flanks of the indentations that increases in a direction from the edge of the at least one optical body to the center of the at least one optical body and a prism angle (.delta.) that decreases in a direction from the edge to the center of the at least one optical body. ### Claim 7 (depends on 4) Optical system in accordance with claim 4, wherein the at least one optical body is a circular disk. ### Claim 8 (depends on 7) Optical system in accordance with claim 7, wherein the indentations are concentric circles on the structured surface side of the at least one optical body. ### Claim 9 (depends on 8) Optical system in accordance with claim 8, wherein the indentations arranged on the structured surface side of the at least one optical body are of notch shape with a slope angle (.alpha.) of the flanks of the indentations that increases in a direction from the edge to the center of the at least one optical body and a prism angle (.delta.) that decreases in a direction from the edge to the center of the at least one optical body.