Patent ID: 7304798

Claim:
A spectroscopic apparatus that performs splitting of light, comprising: an optical input-processing section that forms a filtered transmitted light, and collects the filtered transmitted light, and collects the filtered transmitted light to generate a collected beam, the optical input-processing section including a bandpass filter through which an input light is transmitted to form a filtered transmitted light; an optic that includes a first reflection surface and a second reflection surface and causes the collected beam incident thereon to undergo multiple reflections within an inner region between the first reflection surface and the second reflection surface, to thereby cause split beams to be emitted via the second reflection surface; and a control section that variably controls at least one of a filter characteristic of the bandpass filter and an optical length through the optic, wherein the optical input-processing section includes a lens for forming the input light into a collimated light, a front-side condenser lens that collects the filtered transmitted light in a one-dimensional direction to thereby emit the collected beam, and the bandpass filter disposed between the lens and the front-side condenser lens, for passing only a wavelength band of the collimated light at one period, to thereby output the filtered transmitted light.