Photodiode array and signal readout method for the same

Abstract

An easy and inexpensive signal readout method is provided for a photodiode array consisting of n pieces of photodiodes whose signals are sequentially read out from the first through nth photodiodes. The method includes a canceling process that is performed one or more times before performing a complete readout operation for sequentially reading out signals from all the photodiodes, and the canceling process includes the steps of sequentially reading out signals of a predetermined number of photodiodes starting from the first photodiode to cancel the signals of these photodiodes and then returning to the readout of the signal of the first photodiode. According to this method, it is possible to easily set an appropriate charging time for each photodiode and yet prevent the photodiodes from becoming saturated.

Description

technical field [0001] The present invention relates to a photodiode array created by arranging a plurality of photodiodes. The invention also relates to a signal reading method of the photodiode array. Background technique [0002] Photodiode arrays are commonly used for light detection in spectrophotometers or other devices because they collectively receive the spectrum dispersed by a diffraction grating or similar device, thereby detecting light intensities over a wide range of wavelengths almost simultaneously device. [0003] In a photodiode array, each photodiode produces a current, voltage, or other form of signal corresponding to the intensity of light falling on it. Then, the signals of the photodiodes are sequentially read by the signal processing circuit and processed one by one. There are two main methods for separately reading signals from photodiodes: real-time reading and memory reading. [0004] In the real-time readout method, an amplifier is provided fo...

AI Technical Summary

Problems solved by technology

However, the drawback of this system is that it is difficult to improve the signal-to-noise ratio (S / N) since the signal strength depends only on the intensity of the incident light

However, there are several problems with this approach: for example, increasing the number of photodiodes requires more complex scheduling of the timing of reading signals from all photodiodes without changing each photodiode read cycle

Therefore, with a processor with low processing power (e.g., a single processing circuit) and a photodiode array with a large area, some photodiodes may saturate even when the minimum read period is set to the minimum value

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