The Study Of Non-Mechanical Light-beam Scanning Method

Scanning measurement is a basic means to achieve high precision geometricmeasurement. However, the scanning device has a congenital defect which is thepresence of a mechanical scanning device, thus, it has some issues such as wear,vibration, temperature sensitive. This paper advances two methods to realize non-mechanical light-beam scanning, which are based on optical phased array technologyand acousto-optic deflection technology. The method has the advantages of theprinciple, it eliminates the inherent defect of rotary machine structure on themeasurement accuracy, speed, controllability, and stability.Optical phase array technology is a new type of electro-optical scanning technology,with the advantages of faster scanning speed, random access, stable performance andhigh resolution. This article describes the traditional method of beam scanning, thenputs forward a innovative scanning method which is optical phased array light-beam.First, we describe the history of the development of optical phased array, and then wediscuss the basic principles of the regular optical phased array. However, themodulation unit’size of the regular optical phased array can only be equal to or lessthan half of the wavelength of incident light, otherwise, there will be accompanied bya accompanying beam, affecting the quality of the scanning beam. However, themodulation unit’size is too small, will bring a series of problems, so we studyirregular optical phased array method, giving theoretical analysis and the theoreticalmodel, on this basis, we put forward the equal irregular optical phased array theory. Inthe irregular optical phased array, the modulation unit’size will be no longer limitedby the wavelength of incident light, it can be larger than the wavelength of incidentlight few times or even a hundred of times. According to the principles of the equalirregular optical phased array,we design a kind of optical phased array device, andgive the model construction and theoretical analysis.Finally, we confirm this opticalphased array device can achieve light-beam scanning.Finally, we described the light-beam scanning method based on acousto-opticdeflection. We chose a kind of acousto-optic deflector producted by the Britishcompany Gooch&Housego. The acousto-optic deflector is formed by acousto-optic medium and piezoelectric transducer. We use the acousto-optic deflector to build anexperimental platform.