Infrared sensor, sensing system, and infrared sensing method

An infrared sensing method comprising:

• generating an output signal from an output pixel on the basis of outputs from infrared photodetectors, the output pixel including infrared photodetectors, the outputs corresponding one-to-one to the infrared photodetectors;
• switching each of the infrared photodetectors between a first state and a second state independently in a predetermined period, the first state being a state in which the infrared photodetector is able to change in temperature in response to receiving infrared radiation, the second state being a state in which the infrared photodetector is maintained at a predetermined temperature;
• maintaining each of the infrared photodetectors in the first state for a specific amount of time in the predetermined period;
• switching the infrared photodetectors from the second state to the first state sequentially in the predetermined period, the switches from the second state to the first state corresponding one-to-one to the infrared photodetectors, a time interval provided between a first switch among the switches and a second switch among the switches being a predetermined time interval, the second switch being provided immediately after the first switch among the switches;
• and
• switching the infrared photodetectors from the first state to the second state sequentially in the predetermined period,
• wherein a total number of the photodetectors is N,
• wherein N is an integer greater than or equal to 2,
• wherein the predetermined time interval divided by the period is greater than or equal to 1/(N+1) and less than or equal to 1/(N−1).

An infrared sensor comprising:

• a pixel including a first cell including a first infrared photodetector, . . . , and an Nth cell including an Nth infrared photodetector;
• and
• a first thermoelectric cooler that cools the first infrared photodetector, . . . , and an Nth thermoelectric cooler that cools the Nth infrared photodetector,
• wherein the first thermoelectric cooler is supplied with an electric current from a time m×T to a time {m×T+ta(1)}, and from a time {m×T+ta(1)+tb(1)} to a time (m+1)×T, and as a result, the first infrared photodetector is cooled, . . . , and the Nth thermoelectric cooler is supplied with an electric current from the time m×T to a time {m×T+ta(N)}, and from a time {m×T+ta(N)+tb(N)} to the time (m+1)×T, and as a result, the Nth infrared photodetector is cooled,
• wherein the first thermoelectric cooler is supplied with no electric current from the time {m×T+ta(1)} to the time {m×T+ta(1)+tb(1)}, . . . , and the Nth thermoelectric cooler is supplied with no electric current from the time {m×T+ta(N)} to the time {m×T+ta(N)+tb(N)},
• wherein N is a natural number greater than or equal to 2,
• wherein m is an integer greater than or equal to 0,
• wherein {1/(N+1)}≤{(ta(2)−ta(1))/T}≤{1/(N−1)}, . . . , and {1/(N+1)}≤{(ta(N)−ta(N−1))/T}≤{1/(N−1)},
• wherein the pixel outputs a signal Om,
• wherein the signal Om is based on one or more detection values detected by the first cell from the time {m×T+ta(1)} to the time {m×T+ta(1)+tb(1)}, . . . , and the signal Om is based on one or more detection values detected by the Nth cell from the time {m×T+ta(N)} to the time {m×T+ta(N)+tb(N)}, and
• wherein the signal Om is not based on one or more detection values detected by the first cell from the time m×T to the time {m×T+ta(1)}, and is not based on one or more detection values detected by the first cell from the time {m×T+ta(1)+tb(1)} to the time (m+1)×T, . . . , and the signal Om is not based on one or more detection values detected by the Nth cell from the time m×T to the time {m×T+ta(N)}, and is not based on one or more detection values detected by the Nth cell from the time {m×T+ta(N)+tb(N)} to the time (m+1)×T.