Moving head light is most important consideration in the design of optical systems is the utilization rate of the luminous flux of the light source. Specific performance indicators include light intensity, uniformity, saturation, and spot size. There are two factors that affect the above indicators, one is the light source, and the other is the optical system structure and material selection. Domestic and foreign manufacturers and users basically recommend OSRAM or PHILIPS1200W short-arc double-ended metal gas discharge lamps. Its characteristics are compactness, high brightness, high color temperature, good color rendering, and the light source can maintain a relatively stable color temperature during the dimming process. The disadvantage is that the layering problem of the filler in the lamp tube, that is, the filler appears in the arc imaging ribbon or condenses in the arc tube, forming a shadow effect, needs to be controlled to the minimum range during the design of the optical structure. In the optical structure, in order to obtain a uniform mixed beam, a parabolic reflector can be used. To collect a divergent or narrow beam, a reflector with scale processing or surface texture should be selected. A reflector system made of specular reflective materials is better than a refraction system. When you need to get several beams from a light source, you can use a combination of prism or lens refraction system. At present, in the optical design of 1200W moving head computer lights at home and abroad, the lens combination method is adopted, which is composed of aspherical (that is, parabolic) quartz lenses.
The most important feature of the parabolic lens is to place a point light source on the focal point, which will get a parallel beam. In the design of the optical path, it is also necessary to consider the correlation between the light intensity distribution curve, shape and the size of the light source, the size of the aperture of the reflective lens, and the shape of the light source.
