High-speed light sensing apparatus

An optical apparatus comprising:

• an absorption layer comprising a photodetection region configured to absorb photons and to generate photo-carriers in response to the absorbed photons;
• one or more first switches each controlled by a first control signal, the one or more first switches each configured to collect at least a first portion of the photo-carriers based on the first control signal;
• and
• one or more second switches each controlled by a second control signal, the one or more second switches each configured to collect at least a second portion of the photo-carriers based on the second control signal, wherein the second control signal is different from the first control signal, and wherein the first portion of the photo-carriers and the second portion of the photo-carriers are of a same type of carriers,
• wherein the one or more first switches each comprise:
• a first well region having a first polarity;
• a first doped region having a second polarity opposite to the first polarity, at least a portion of the first doped region having the second polarity being formed in the first well region having the first polarity, and the first doped region having the second polarity being controlled by the first control signal;
• and
• a second doped region having the first polarity coupled to a first readout integrated circuit;
• and
• wherein the one or more second switches each comprise:
• a second well region having the first polarity;
• a third doped region having the second polarity, at least a portion of the third doped region being formed in the second well region, and the third doped region being controlled by the second control signal;
• and
• a fourth doped region having the first polarity coupled to a second readout integrated circuit.

A three-dimensional imaging system, comprising:

• a transmitter unit comprising a light source for generating photons and directing the photons to a three-dimensional object;
• and
• a receiver unit comprising an image sensor, the image sensor comprising multiple pixels supported by a silicon substrate, each pixel comprising an absorption layer having a different composition from the silicon substrate, the absorption layer comprising a photodetection region configured to absorb photons reflected from the three-dimensional object and to generate photo-carriers in response to the absorbed photons,
• wherein each of the multiple pixels is configured so that at least some of the photons reflected from the three-dimensional object are transmitted through the silicon substrate into the photodetection region of the absorption layer,
• wherein the absorption layer substantially absorbs photons in the near infrared (NIR) region for photodetection and the silicon substrate substantially absorbs photons in a shorter wavelength region compared to the NIR region for optical filtering.