Multispectral ranging and imaging systems
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 ranging and imaging system comprising:
a device that includes a sensor array, the sensor array having a plurality of sensor channels including one or more LIDAR sensor channels and one or more ambient-light sensor channels, wherein the sensor channels are arranged in a plurality of sensor rows, each sensor row including:
at least one LIDAR sensor channel; and
a set of one or more ambient-light sensor channels, wherein each ambient-light sensor channel includes:
a channel input aperture;
a photosensor; and
a channel-specific optical filter that selectively passes light having a channel-specific property to the photosensor, and
a bulk optic module disposed in front of the sensor array and configured to direct light onto the sensor array to form an image of a field of view, the image including ambient-light intensity from the ambient-light sensor channels and depth information from the LIDAR sensor channels.
2. The ranging and imaging system of claim 1 wherein the LIDAR sensor channels and the ambient-light sensor channels are arranged in a focal plane of the bulk optic module and displaced laterally from each other.
3. The ranging and imaging system of claim 1 wherein the sensor channels of the plurality of sensor channels have non-overlapping fields of view in a far field.
4. The ranging and imaging system of claim 1 wherein the sensor array is formed in a single integrated circuit.
5. The ranging and imaging system of claim 1 further comprising:
a controller to operate the sensor array to generate image data for a field of view.
6. The ranging and imaging system of claim 1 wherein the set of one or more ambient-light sensor channels in each sensor row includes a first ambient-light sensor channel that is sensitive to a visible-light portion of the electromagnetic spectrum.
7. The ranging and imaging system of claim 1 wherein the set of one or more ambient-light sensor channels in each sensor row includes:
a first ambient-light sensor channel that is sensitive to red light;
a second ambient-light sensor channel that is sensitive to green light; and
a third ambient-light sensor channel that is sensitive to blue light.
8. The ranging and imaging system of claim 1 wherein at least some of the ambient-light sensor channels further include a channel-specific micro-optic element having a prescription that is based at least in part on the channel-specific optical filter.
9. The ranging and imaging system of claim 1 further comprising:
a plurality of channel-specific micro-optic elements, each channel-specific micro-optic element being disposed in front of a different one of the sensor channels and having an optical prescription that is different for different sensor channels.
10. The ranging and imaging system of claim 9 wherein the optical prescription for a particular one of the channel-specific micro-optic elements is based at least in part on an optical property of the bulk optic module.
11. The ranging and imaging system of claim 9 wherein the bulk optic module exhibits chromatic aberration and wherein the optical prescription for at least some of the sensor channels is based in part on the channel-specific optical filter and in part on the chromatic aberration of the bulk optic module.
12. The ranging and imaging system of claim 9 wherein the bulk optic module has a curved focal plane and wherein the optical prescription of each of the channel-specific micro-optic elements compensates for an offset between a location of the aperture and a corresponding location on the curved focal plane.
13. The ranging and imaging system of claim 12 wherein the optical prescription of each channel-specific micro-optic element is a function of a radial distance in an aperture plane from an optical axis of the bulk optic module to the corresponding aperture.
14. The ranging and imaging system of claim 12 wherein the channel-specific micro-optic elements disposed in front of different apertures have optical prescriptions with different focusing powers.
15. The ranging and imaging system of claim 12 wherein the channel-specific micro-optic elements disposed in front of different channels have different standoff distances from the aperture plane.
16. The ranging and imaging system of claim 1 wherein each of the ambient-light sensor channels and the LIDAR sensor channels includes one or more single-photon avalanche diodes (SPADs).