Abstract: Diffraction-grating-based depth imaging systems and methods for pixel crosstalk mitigation are disclosed. The system includes a transmissive diffraction mask (TDM) and an underlying image sensor. The TDM receives light from a scene and generates diffracted light encoding angle-of-incidence information, which is detected by the image sensor including a plurality of pixels. The TDM has a grating structure that spatially maps the diffracted light onto distinct pixel groups, including bright-positive pixels that receive a portion of the diffracted light and exhibit a pixel response that increases with angle of incidence, bright-negative pixels that receive another portion of the diffracted light and exhibit a pixel response that decreases with angle of incidence, and dark pixels that receive substantially no diffracted light. The dark pixels are interspersed among the bright-positive and bright-negative pixels to mitigate pixel crosstalk, enhancing the accuracy and contrast of depth measurements.

Abstract: A method of managing power usage of a depth imaging system including an image sensor having an array of pixels configured to detect light incident from a scene and an optical encoder configured to modulate the incident light detected by the pixels in accordance with an angle of incidence of the incident light. The method includes operating the system in a lower power mode corresponding to a first power consumption level, including capturing, with the pixels, image data of the scene having angle-dependent information encoded therein by the optical encoder, and identifying, based on the angle-dependent information, signature information in the image data indicative of a detection of an object within a specified depth range. The method also includes, in response to identifying the signature information, transitioning to operating the system in a higher power mode corresponding to a second power consumption level higher than the first power consumption level.

Abstract: A method of managing power usage of a depth imaging system including an image sensor having an array of pixels configured to detect light incident from a scene and an optical encoder configured to modulate the incident light detected by the pixels in accordance with an angle of incidence of the incident light. The method includes operating the system in a lower power mode corresponding to a first power consumption level, including capturing, with the pixels, image data of the scene having angle-dependent information encoded therein by the optical encoder, and identifying, based on the angle-dependent information, signature information in the image data indicative of a detection of an object within a specified depth range. The method also includes, in response to identifying the signature information, transitioning to operating the system in a higher power mode corresponding to a second power consumption level higher than the first power consumption level.

Abstract: A method of lens position determination in an imaging system is disclosed. The system can include an imaging lens, an image sensor, and an optical encoder interposed between the imaging lens and the image sensor. The method can include capturing image data from a scene by detecting, with the array of pixels of the image sensor, light incident from the scene having passed through the imaging lens and the encoder, the encoder being configured to encode angle-dependent information about the incident light in the image data in accordance with an angular response of the encoder. The method can also include generating a uniform-field image from the captured image data, the uniform-field image having an intensity profile that varies with image position in accordance with the encoded angle-dependent information. The method can further include determining current lens position information about the imaging lens from the intensity profile of the uniform-field image.