Optical Bench Design
The heart of the AvaSpec fiber optic spectrometer is an optical bench with 45, 50 or 75 mm focal length, developed in a symmetrical Czerny-Turner design.
Light enters the optical bench through a standard SMA905 connector and is collimated by a spherical mirror. A plane grating diffracts the collimated light; a second spherical mirror focuses the resulting diffracted light. An image of the spectrum is projected onto a 1-dimensional linear detector array. The optical bench has a number of components installed inside, allowing a wide variety of different configurations, depending on the intended application. The choice of these components such as the diffraction grating, entrance slit, order sorting filter, and detector coating have a strong influence on system specifications. Sensitivity, resolution, bandwidth and stray light are further discussed in the following paragraphs.