Methods and Systems Utilizing Multiple Wavelengths for Position Detection
OwnerPaul Marsoninventor
Life of this patent
Estimating the term…
Abstract
A position detection system can utilize multiple optical responses to a detection scene, such as by using multiple different patterns of light for imaging a given detection scene. The multiple patterns can include a first pattern containing image data that can be used to separate reflected light from retroreflected light in a second pattern of light. This can be used to reduce errors, such as false detections due to directly-reflected light, and/or can be used for identification of objects in the touch detection scene when the objects themselves are optically configured to appear differently in different patterns of light.
Claims25
A device, comprising:
- an optical detector configured to generate an image representing light from a detection area;
- and
- processing circuitry interfaced to the optical detector and configured to:
- obtain a signal representing a first pattern of light from the detection area in response to light having a first wavelength being directed into the area,
- obtain a signal representing a second pattern of light from the detection area in response to light having a second wavelength being direct into the detection area, and
- produce an output signal by subtracting the signal representing the second pattern of light from the signal representing the first pattern of light.
A method, comprising:
- receiving, by a detector, light representing a first optical response of a detection scene and generating a first detection signal;
- receiving, by the detector, light representing a second optical response of the detection scene and generating a second detection signal;
- and
- based on the light representing the first and second optical responses, determining at least one of a location of an object in the detection scene or an identity of an object in the detection scene.
A position detection system, comprising:
- a reflective member positioned along at least part of at least one edge of a detection area, the reflective member configured to reflect light of a first wavelength and to attenuate light of a second wavelength;
- a detector positioned to image at least the reflective member;
- and
- an illumination system configured to direct light having the first wavelength and the second wavelength into the detection area.
A method, comprising:
- receiving, by a detector, light representing a first optical response of a detection scene and generating a first detection signal;
- receiving, by the detector, light representing a second optical response of the detection scene and generating a second detection signal;
- and
- based on the light representing the first and second optical responses, determining, by processing hardware interfaced to the detector, an identity of an object in the detection scene by comparing a selected portion of a first image representing the first optical responds with a corresponding portion of a second image representing the second optical response and, based on the comparison, identifying whether an expected intensity pattern is found, the identity of the object being an identity associated with the expected intensity pattern.
Dependencies are inferred from the claim text.