| 摘要 |
In a particle detector, a stream entraining particles to be measured is passed through a laser beam. Light scattered in two different directions from the laser beam by particles are detected by photodetectors and a coincidence circuit detects simultaneous pulses generated by both photodetectors to discriminate against noise and to disable the integration function in baseline control circuits for preamplifiers amplifying the output signals from the photodetectors. In an alternative embodiment arrays of photodetectors are arranged to detect light scattered in different directions from the sample stream. Optics are provided to focus light scattered from different positions in the sample stream upon different photodetectors in each array so that simultaneous particles in the sample stream can be detected.
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