The Fabry-Pérot interferometers offered by ALPHALAS are high-resolution spectroscopic instruments having applications in spectral analysis of narrowband light sources like gas discharge lamps and lasers. These are especially useful for analyzing the spectral content of pulsed lasers because they provide single-shot measurement. The interferometers consist of two high-precision mirrors with a flatness better than Lambda/40 over 90% of the aperture, having broadband coatings and spacers of different thickness. The working aperture is either 22 mm or 48 mm and the reflectivity finesse is > 120. The standard spectral range is 450 nm … 1100 nm, other on request. Combined with our CCD linear array, these interferometers form a versatile spectral analysis system.