Compact light sensor

An imaging device, comprising:

• a lens disposed along an optical axis and configured to receive light;
• a first light source and a second light source, wherein:
• the first light source and the second light source are configured to shine light so that a portion of the light is backscattered by an object and received by the lens,
• the first light source emits light that is substantially limited to a first spectral range,
• the second light source emits light that is substantially limited to a second spectral range, and
• the first spectral range is substantially non-overlapping with the second spectral range;
• a plurality of photo-sensors;
• an optical path assembly comprising a plurality of beam splitters in optical communication with the lens and the plurality of photo-sensors, wherein:
• each respective beam splitter in the plurality of beam splitters is configured to split the light received by the lens into at least two optical paths,
• a first beam splitter in the plurality of beam splitters is in direct optical communication with the lens and a second beam splitter in the plurality of beam splitters is in indirect optical communication with the lens through the first beam splitter, and
• the plurality of beam splitters collectively split light received by the lens into a plurality of optical paths, wherein each respective optical path in the plurality of optical paths is configured to direct light to a corresponding photo-sensor in the plurality of photo-sensors through the respective multi-bandpass filter covering the corresponding photo-sensor;
• a plurality of multi-bandpass filters, wherein each respective multi-bandpass filter in the plurality of multi-bandpass filters covers a corresponding photo-sensor in the plurality of photo-sensors thereby selectively allowing a different corresponding spectral band of light, from the light received by the lens and split by the plurality of beam splitters, to pass through to the corresponding photo-sensor;
• and
• a controller configured to capture a plurality of images from the plurality of photo-sensors by performing a method including:
• (A) illuminating the object a first time using the first light source;
• (B) capturing a first set of images with the plurality of photo-sensors during the illuminating (A), wherein the first set of images includes, for each respective photo-sensor in the plurality of photo-sensors, an image corresponding to a first spectral band transmitted by the corresponding multi-bandpass filter, wherein the light falling within the first spectral range includes light falling within the first spectral band of each multi-bandpass filter in the plurality of multi-bandpass filters;
• (C) extinguishing the first light source;
• (D) illuminating the object a second time using the second light source;
• and
• (E) capturing a second set of images with the plurality of photo-sensors during the illuminating (D), wherein the second set of images includes, for each respective photo-sensor in the plurality of photo-sensors, an image corresponding to a second spectral band transmitted by the corresponding multi-bandpass filter, wherein the light falling within the second spectral range includes light falling within the second spectral band of each multi-bandpass filter in the plurality of multi-bandpass filters.