Subpixel apertures for channels in a scanning sensor array
A multispectral sensor array can include a combination of ranging sensor channels (e.g., LIDAR sensor channels) and ambient-light sensor channels tuned to detect ambient light having a channel-specific property (e.g., color). The sensor channels can be arranged and spaced to provide multispectral images of a field of view in which the multispectral images from different sensors are inherently aligned with each other to define an array of multispectral image pixels. Various optical elements can be provided to facilitate imaging operations. Light ranging/imaging systems incorporating multispectral sensor arrays can operate in rotating and/or static modes.
1. A sensor array having a plurality of sensor rows, each sensor row comprising:
a group of two or more enhanced-resolution ambient-light sensor channels sensitive to a range of wavelengths, wherein each enhanced-resolution ambient-light sensor channel in the group includes:
a channel-specific input aperture, wherein the channel-specific input apertures of different enhanced-resolution ambient-light sensor channels in the group expose different portions of a channel area; and
a photosensor;
a logic circuit to determine a plurality of subpixel light intensity values based on intensity data from the photosensors in the group of enhanced-resolution ambient-light sensor channels; and
a controller configured to perform a scanning operation that exposes the sensor array to different areas within a field of view at different times such that each ambient-light sensor channel in the group of two or more enhanced-resolution ambient-light sensor channels in a particular row is exposed to a same pixel area within the field of view at different times.
2. The sensor array of claim 1 wherein each enhanced-resolution ambient-light sensor channel in the group further includes an optical filter that selectively passes light having a specific property, wherein the specific property is the same for every enhanced-resolution ambient-light sensor channel in the group.
3. The sensor array of claim 1 wherein the different portions of the channel area exposed by the apertures of different enhanced-resolution ambient-light sensor channels in the group are non-overlapping portions of the channel area.
4. The sensor array of claim 3 wherein the group of enhanced-resolution ambient-light sensor channels includes four enhanced-resolution ambient-light sensor channels and the non-overlapping portions correspond to different quadrants of the channel area.
5. The sensor array of claim 1 wherein the different portions of the channel area exposed by the apertures of different enhanced-resolution ambient-light sensor channels in the group are overlapping portions of the channel area.
6. The sensor array of claim 5 further comprising an arithmetic logic circuit to decode intensity values for a set of non-overlapping portions of the channel area based on sensor data from the group of two or more enhanced-resolution ambient-light sensor channels.
7. The sensor array of claim 5 wherein the group of two or more enhanced-resolution ambient-light sensor channels further includes a first high-resolution ambient-light sensor channel having an aperture that exposes the entire channel area.
8. The sensor array of claim 7 further comprising an arithmetic logic circuit to decode intensity values for a set of non-overlapping portions of the channel area based on sensor data from the group of two or more enhanced-resolution ambient-light sensor channels.
9. The sensor array of claim 1 wherein each sensor row further comprises a LIDAR sensor channel spatially registered with the group of enhanced-resolution ambient-light sensor channels.
10. The sensor array of claim 9 wherein the LIDAR sensor channels provide depth data for a depth image having a first resolution and the enhanced-resolution ambient-light sensor channels provide an intensity image having a second resolution that is higher than the first resolution in at least one dimension.
11. The sensor array of claim 10 wherein the second resolution is higher than the first resolution in both a row-wise dimension and a dimension transverse to the row-wise dimension.
12. A scanning imaging system comprising:
a sensor array including:
a group of two or more enhanced-resolution ambient-light sensor channels sensitive to a range of wavelengths, wherein each enhanced-resolution ambient-light sensor channel in the group includes:
a channel-specific input aperture, wherein the channel-specific input apertures of different enhanced-resolution ambient-light sensor channels in the group expose different portions of a channel area;
a photosensor; and
a plurality of registers to accumulate photon counts from the photosensor during a time interval that is subdivided into a plurality of time bins, wherein each of the plurality of registers accumulates photon counts during a different one of the plurality of time bins; and
an arithmetic logic circuit to compute a plurality of subpixel light intensity values based on the photon counts accumulated in the plurality of registers of all of the enhanced-resolution ambient-light sensor channels in the group; and
a controller configured to perform a scanning operation that exposes the sensor array to different areas within a field of view at different times such that each ambient-light sensor channel in the group of two or more enhanced-resolution ambient-light sensor channels in the group of two or more enhanced-resolution ambient-light sensor channels is exposed to a same pixel area within the field of view at different times.
13. The scanning imaging system of claim 12 wherein each enhanced-resolution ambient-light sensor channel in the group further includes an optical filter that selectively passes light having a specific property, wherein the specific property is the same for every enhanced-resolution ambient-light sensor channel in the group.
14. The scanning imaging system of claim 12 further comprising:
a LIDAR sensor channel spatially registered with the group of enhanced-resolution ambient-light sensor channels.
15. The scanning imaging system of claim 14 wherein the LIDAR sensor channels provide depth data for a depth image having a first resolution and the enhanced-resolution ambient-light sensor channels provide an intensity image having a second resolution that is higher than the first resolution in both a row-wise dimension and a dimension transverse to the row-wise dimension.
16. The scanning imaging system of claim 12 wherein the different portions of the channel area exposed by the apertures of different enhanced-resolution ambient-light sensor channels in the group are non-overlapping portions of the channel area.
17. The scanning imaging system of claim 12 wherein the different portions of the channel area exposed by the apertures of at least two of the enhanced-resolution ambient-light sensor channels in the group are overlapping portions of the channel area.
18. The scanning imaging system of claim 12 wherein the group of two or more enhanced-resolution ambient-light sensor channels includes four ambient-light sensor channels, the plurality of registers includes four registers, and the arithmetic logic circuit computes sixteen subpixel light intensity values.
19. The scanning imaging system of claim 18 wherein the channel-specific input aperture of a first one of the enhanced-resolution ambient-light sensor channels exposes a quarter of the channel area and wherein the respective channel-specific input apertures of a second, a third, and a fourth one of the enhanced-resolution ambient-light sensor channels each exposes a different portion of the quarter of the channel area.