Measuring wavelength of monochromatic optical beam - displays ratio of outputs of different spectral sensitivity directly to photodiodes

摘要

The method is for measuring the wavelength of a monochromatic optical beam rapidly and simply is esp. applicable the development of arrangements contg. optical waveguides or optical fibres. It enables measurements of relatively high accuracy to be made. The beam is directed to two photo-receivers (3,4) with known different spectral sensitivity characteristics. The ratio of the receiver output signals is converted into a proportional voltage which is displayed directly in a measurement instrument (6) calibrated in wavelength. The conversion of the output signal ratio into a voltage is performed in a conventional divider circuit. The associated equipment is extremely economical to make and very simple to operate, yet it produces sufficient accuracy and an easily readable indication. Different photodiode receivers can be used for different wavelength ranges.