LEOI-94 is a manually operated monochromator that utilizes a dial for wavelength selection. Both the entrance and exit slits are straight. The width of both slits is continuously adjustable from 0 to 2 mm with a reading resolution of 0.01 mm.
This monochromator selects the wavelength output by combing the scale reading of a knob with a wavelength reading ruler. The wavelength reading ruler marks a wavelength range from 0 to 900 nm with 1 nm per division while the knob provides 0.1 nm per division. Wavelength precision is high and reliable based on this mechanism.