Theoretical Study for Effect Temperature on Fractal Optical Modulator by Using Modulation Transfer Function

Abstract

Optical modulator or chopper is an important part in an optical system. It is a device, which changes the angle between the vision line of the target and coordinate to an electrical signal. This paper has been designed as a new model of the fractal optical modulator. A new optical modulator involves two cycles (inner and outer). Each cycle of them consists of eighteen sections. Any designer may be known that the sections of the optical modulator become two parts, nine sections consider is transparent and other section nine is opaque to light. There are two parameters have taken to design the optical modulator, first factor is the shape and second factor is the section number. A new chopper is made from semiconductor material such as Cadmium Telluride by using the fractal function. A chopper is created by building a computer program using the visual basic language. For the importance of the modulation transfer function in testing and evaluating optical systems, it becomes the dependent measurement to know the optical systems efficiency. It has been studied for optical systems with a circular aperture, where that function could evaluate the image efficiency for point object of image plane at different magnitude of the temperature and wavelengths. In this research, the fractal optical modulator has been designed of semiconductor material by using the fractal function. Then evaluating the values of MTF at different values of the wavelength and temperatures. Also, we studied the relation between spatial frequency and MTF.