Optical flats are made of optical materials that have been optically polished on the surface.
Optical Flats are used to measure the flatness error and grinding performance of high-smooth surfaces, and have high-precision flatness. Generally used alone.
Commonly used optical flat include plane flat , long flat and parallel flat. It is suitable for use in optical processing plants, measurement rooms of factories and mines, precision processing workshops, and on-site testing of valve sealing surfaces. It is also suitable for flatness testing in colleges and universities, scientific research and other units.
Usually there are two surface types: λ/10 and λ/20, and the parallel difference accuracy can be <1 arc second. Each optical flat of BOTE OPTICS is finely polished and tested using a Zygo interferometer to ensure surface accuracy.
Optical Flat uses the phenomenon of light wave interference to measure flatness error, so its measurement method is called optical flat interference method, also called technical light wave interference method. When measuring, place the optical flat on the surface to be measured and form a small wedge angle θ with the surface to be measured. Interference fringes will be produced when illuminated by a monochromatic light source. The position of the interference fringes is related to the incident angle of the light. If the incident light is perpendicular to the measured surface and the gap between the optical flat and the measured surface is very small, the light reflected by the optical flat measuring surface P and the light reflected by the measured surface will interfere at the measuring surface P and appear bright or dark. interference fringes. If under white light, colored interference fringes will appear. If the interference fringes are straight, parallel to each other, and evenly distributed, it means that the flatness of the measured surface is good; if the interference fringes are curved, it means that the flatness is not good. The error value is f= (v/ω)×(λ/2).
BOTE OPTICS provides uncoated double-sided and single-sided optical flat of various sizes with bases of K9 optical glass and UV fused silica. Fused silica is suitable for UV applications.