# US 2001/0022342 A1 · Optical Transducer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2001/0022342 A1 - Document ID: US20010022342A1 - Status: Published application - Kind: A1 - Application number: 09/828,101 - Filed: 2001-04-07 - Published: 2001-09-20 - Earliest claimed: 1998-07-15 - Inventors: Alvin R. Wirthlin - Web page: https://patentgrep.com/patent/US20010022342A1 ## CPC - G01F 23/2925: {using electrical detecting means} - G01C 9/06: Electric or photoelectric indication or reading means - G01D 5/26: characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light - G01F 23/292: Light {, e.g. infrared or ultraviolet} - G01F 23/2922: {with light-conducting sensing elements, e.g. prisms} - G01F 23/686: {using opto-electrically actuated indicating means} - G01P 3/36: Devices characterised by the use of optical means, e.g. using infrared, visible, or ultraviolet light (G01P3/68 takes precedence; gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams G01C19/64) - G01P 13/002: {with electrical coupling to the indicating devices} - G01P 15/006: {by making use of fluid seismic masses} - G01P 15/0888: {for indicating angular acceleration} - G01P 15/093: by photoelectric pick-up - G01C 2009/066: {optical} - G01F: MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) ## Abstract An optical transducer comprises a light source for emitting radiant energy, a base member, and an elongate light collector positioned for receiving radiant energy from the light source. The elongate light collector comprises a tunnel formed in the base member and a collector window that extends along a length of the tunnel. Radiant energy projected by the light source is received in the tunnel through the window and is transmitted along a length of the tunnel. A portion of the transmitted radiant energy exits the tunnel to thereby vary the intensity of light along the tunnel length. At least one photosensor is positioned for detecting the amount of radiant energy at a location in the tunnel. In this manner, the intensity of radiant energy at the tunnel location is indicative of at least relative position between the incident radiant energy and the at least one photosensor. ## Claims ### Claim 1 An optical transducer, comprising: a light source for emitting radiant energy; a base member; an elongate light collector positioned for receiving radiant energy from the light source, the elongate light collector comprising a tunnel formed in the base member and a collector window that extends along a length of the tunnel, such that radiant energy projected by the light source through the window is incident on the tunnel and transmitted along a length of the tunnel with a portion of the transmitted radiant energy exiting the tunnel to thereby vary the intensity of light along the tunnel length; and at least one photosensor positioned for detecting the amount of radiant energy at a location in the tunnel; wherein the intensity of radiant energy at the tunnel location is indicative of at least relative position between the incident radiant energy and the at least one photosensor. ### Claim 2 (depends on 1) An optical transducer according to claim 1, wherein the window is formed as an open gap in the base member. ### Claim 3 (depends on 2) An optical transducer according to claim 2, wherein a width of the gap is less than a cross dimension of the tunnel. ### Claim 4 (depends on 1) An optical transducer according to claim 1, wherein a width of the window is less than a cross dimension of the tunnel. ### Claim 5 (depends on 1) An optical transducer according to claim 1, wherein the light source and light collector are relatively movable to thereby vary the intensity of radiant energy at the tunnel location. ### Claim 6 (depends on 1) An optical transducer according to claim 1, and further comprising a light blocking member extending between the light source and at least a portion of the elongate light collector for blocking at least a portion of the radiant energy from the light collector, the light blocking member and light collector being relatively movable for varying the position of the radiant energy incident on the light collector to thereby vary the amount of radiant energy transmitted to the tunnel location. ### Claim 7 (depends on 6) An optical transducer according to claim 6, wherein: the base member comprises an elongate, tubular member having a central axis and a bore extending parallel to the central axis, the elongate light collector extending along a length of the tubular member for receiving, at least indirectly, radiant energy from the light source, the light collector having opposite ends such that radiant energy incident on a length of the light collector is transmitted to the light collector ends; the light blocking member being located within the bore for blocking at least a portion of the radiant energy from the light collector, the light blocking member being movable in the bore with respect to the light collector for varying the position of the radiant energy incident on the light collector to thereby vary the amount of radiant energy transmitted to the tunnel location; wherein the amount of radiant energy received by the light collector and detected by the at least one photosensor is indicative of relative movement between the tubular member and the light blocking member. ### Claim 8 (depends on 7) An optical transducer according to claim 7, wherein the light blocking member comprises at least one float that is adapted to ride on an upper surface of a liquid that may be present in the tubular member. ### Claim 9 (depends on 8) An optical transducer according to claim 8, wherein the light source is positioned at an upper end of the tubular member coincident with the bore. ### Claim 10 (depends on 7) An optical transducer according to claim 7, and further comprising a shaft having one end connected to the light blocking member and an opposite end extending out of the tubular member, wherein the amount of radiant energy received by the light collector and detected by the at least one photosensor is indicative of linear shaft movement. ### Claim 11 (depends on 10) An optical transducer according to claim 10, wherein the light blocking member is located between the light source and the at least one photosensor. ### Claim 12 (depends on 6) An optical transducer according to claim 6, wherein the light blocking member comprises an enclosed vial with a fluent light blocking material filling a portion of the vial, a window being formed at a position in the vial absent the fluent material; wherein rotation of the optical transducer causes the fluent material to flow under gravity and thereby change the position of the window of the light blocking member and thus the position of the radiant energy incident on the light collector. ### Claim 13 (depends on 12) An optical transducer according to claim 12, wherein the fluent material comprises a relatively opaque liquid. ### Claim 14 (depends on 13) An optical transducer according to claim 13, wherein the fluent material comprises granular material. ### Claim 15 (depends on 12) An optical transducer according to claim 12, wherein the enclosed vial is arcuate-shaped, and the collector includes an arcuate-shaped section adjacent the vial. ### Claim 16 (depends on 12) An optical transducer according to claim 12, wherein the enclosed vial is ring-shaped, and the light collector includes a ring-shaped section adjacent the vial. ### Claim 17 (depends on 6) An optical transducer according to claim 6, wherein the light blocking member is located between the light source and the at least one photosensor. ### Claim 18 (depends on 17) An optical transducer according to claim 17, wherein the base member is positioned in a liquid and is adapted to extend beyond an upper surface of the liquid, the light blocking member comprising the upper surface of the liquid, such that the amount of radiant energy received by the light collector and detected by the at least one photosensor is indicative of liquid level. ### Claim 19 (depends on 6) An optical transducer according to claim 6, wherein the light blocking member comprises a disk rotatable about a central disk axis and a window formed on the disk, and further wherein the light collector has an arcuate section in alignment with the window of the light blocking member, such that rotation of the disk about the central disk axis with respect to the light collector varies the position of the radiant energy incident on the arcuate section of the light collector to thereby indicate relative angular displacement between the disk and the light collector. ### Claim 20 (depends on 19) An optical transducer according to claim 19, wherein the light collector extends in a continuous circle such that a rotational position of the disk with respect to the light collector can be detected over 360 degrees. ### Claim 21 (depends on 20) An optical transducer according to claim 20, wherein the window of the light blocking member is arranged to project radiant energy into the tunnel at an acute angle with respect to a central axis of the tunnel. ### Claim 22 (depends on 1) An optical transducer according to claim 1, wherein the light source is arranged to project radiant energy into the tunnel at an acute angle with respect to a central axis of the tunnel. ### Claim 23 (depends on 1) An optical transducer according to claim 1, and further comprising a plurality of light collectors in side-by-side relationship, such that movement of the incident radiant energy across and along the light collectors can be detected. ### Claim 24 (depends on 23) An optical transducer according to claim 23, wherein each light collector has opposite ends, and further wherein the at least one photosensor comprises first and second photosensors positioned for detecting the intensity of radiant energy at the opposite ends of each light collector. ### Claim 25 (depends on 1) An optical transducer according to claim 1, wherein the at least one photosensor comprises first and second photosensors positioned for detecting the intensity of radiant energy in the tunnel at spaced locations. ### Claim 26 (depends on 1) An optical transducer according to claim 1, and further comprising a light blocking member having a flexible plate, a first end of the flexible plate being fixedly mounted with respect to the light source and a second free end adjacent the light collector, the free end being movable in response to an applied force to thereby change a length of the light collector exposed to the radiant energy. ### Claim 27 (depends on 1) An optical transducer according to claim 1, and further comprising a light blocking member having a relatively stiff plate, a first end of the plate being rotatably mounted with respect to the light source about a pivot joint and a second free end of the plate being adjacent the light collector, the plate being rotatable about the pivot joint in response to an applied force to thereby change a length of the light collector exposed to the radiant energy. ### Claim 28 (depends on 1) An optical transducer according to claim 1, wherein a portion of the transmitted radiant energy exits the tunnel through the window. ### Claim 29 A method of detecting relative position between a first object and a second object, the method comprising: forming an elongate light collector on the first object, the elongate light collector including a tunnel and a collector window that extends along a length of the tunnel; projecting radiant energy into the tunnel from the second object; transmitting the radiant energy along a length of the tunnel with a portion of the transmitted radiant energy exiting the tunnel to thereby vary the intensity of light along the tunnel length; and detecting the amount of radiant energy at a location in the tunnel; wherein the intensity of radiant energy at the tunnel location is indicative of the relative position between the first and second objects. ### Claim 30 (depends on 29) A method according to claim 29, wherein a portion of the transmitted radiant energy exits the tunnel through the window. ### Claim 31 (depends on 29) A method according to claim 29, wherein the window is formed as an open gap in the base member. ### Claim 32 (depends on 31) A method according to claim 31, wherein a width of the gap is less than a cross dimension of the open channel. ### Claim 33 (depends on 29) A method according to claim 29, wherein a width of the window is less than a cross dimension of the open channel.