Optical measuring instrument, flow cytometer, and radiation counter

A flow cytometer, comprising:

• a light source configured to generate a light pulse, wherein a first light pulse and a second light pulse are generated based on irradiation of the light pulse on an object to be measured;
• a photodiode configured to:
• receive the first light pulse having a first intensity;
• and
• generate an event signal based on a comparison of the first intensity and a threshold value;
• a photodetector configured to:
• receive the second light pulse by a plurality of pixels, wherein
• the second light pulse has a second intensity lower than the first intensity, and
• each pixel of the plurality of pixels includes a photoelectric conversion element and an amplification element;
• accumulate a plurality of charges subjected to photoelectric conversion by the photoelectric conversion element, wherein the plurality of charges is accumulated for a specific period;
• output a voltage as a pixel signal for each pixel of the plurality of pixels through the amplification element based on an amount of the plurality of charges accumulated for the specific period;
• and
• detect a light amount of the second light pulse based on a plurality of pixel signals output from the plurality of pixels, wherein the plurality of pixel signals includes the pixel signal;
• and
• circuitry configured to control the photodetector to allow the plurality of pixels to simultaneously complete the accumulation of the plurality of charges, wherein the accumulation of the charges is completed based on the generation of the event signal.

A radiation counter, comprising:

• a light source configured to generate a light pulse, wherein a first light pulse and a second light pulse are generated based on a ctatc of irradiation of the light pulse on an object to be measured;
• a photodiode configured to:
• receive the first light pulse having a first intensity;
• and
• generate an event signal based on a comparison of the first intensity and a threshold value;
• a photodetector configured to:
• receive the second light pulse by a plurality of pixels, wherein
• the second light pulse has a second intensity lower than the first intensity, and
• each pixel of the plurality of pixels includes a photoelectric conversion element and an amplification element;
• accumulate a plurality of charges subjected to photoelectric conversion by the photoelectric conversion element, wherein the plurality of charges is accumulated for a specific period;
• output a voltage as a pixel signal for each pixel of the plurality of pixels through the amplification element based on an amount of the plurality of charges accumulated for the specific period;
• and
• detect a light amount of the second light pulse based on a plurality of pixel signals output from the plurality of pixels, wherein the plurality of pixel signals includes the pixel signal;
• and
• circuitry configured to control the photodetector to allow the plurality of pixels to simultaneously complete the accumulation of the plurality of charges, wherein the accumulation of the charges is completed based on the generation of the event signal.