Optical sensing apparatus for CO2 jet spray devices

摘要

Optical sensing apparatus (10) for use with a CO2 jet spray nozzle (16) that sprays a plume (15). The apparatus (10) comprises a coherent light source (11) that provides a light beam (11a). A photodiode (12) is disposed such that it detects the light beam (11a) emitted by the coherent light source (11) that passes through the plume (15) sprayed by the CO2 jet spray nozzle (16). A bandpass filter (13) is disposed between the photodiode (12) and the coherent light source (11) that only passes light produced by the coherent light source (11). A controller (17) coupled to the coherent light source (11) and the photodiode (12) that comprises a power supply (26) for providing power to the coherent light source (11) and the photodiode (12). The controller (17) includes a digital voltmeter (22) coupled to the photodiode (12) for displaying a voltage output signal corresponding to the amount of light energy detected by the photodiode (12), and a go/no-go indicator (21) for providing an indication of CO2 snow production.