Portable Multi-purpose Light And Color Measurement Instrument

Photometric and colorimetric measurement,such as luminous flux measurement of all kinds of lamps,luminous density measurement in classrooms and color measure of color TV etc. are commonly used in daily manufacturing. At present,special photometric and colorimetric instruments are available. However,their functions are too simple,and in some situations a number of instruments are need at the same time to perform various photometric and colorimetric measurement. Is it possible to integrate both photometric and colorimetric measurement into a portable instrument where only different detectors are utilized to measure corresponding optical quantities? To satisfy the special need,the development of such a multi-purpose photometric and colorimetric instrument is discussed in this paper.In this paper,advantages and disadvantages of available photometric and colorimetric instruments are discussed first. Then,a novel instrument is developed,which possesses the following characteristics:utilizing LCD display,flexible keyboard control,integrating capability to perform both photometric and colorimetric measurement so long as the photoelectric detector is changed to another one and corresponding software is performed. The paper consists of seven chapters.The first chapter introduces the basic parameters in photometric and colorimetric and the abroad applications of photometric and colorimetric instruments. The research direction of this paper is brought forward on the basis of the introduction.The second chapter briefs the fundamental principles and methods of photometric and colorimetric measurement,including the measurement principia of luminous density,luminous flux,luminance and chrominance.The third chapter briefs the matching theory of photometric and colorimetric detectors,which is the basis of fabricating photoelectric detectors. Then the system is proposed.The forth chapter discusses the hardware design in details,which is the emphasis of the paper. In mainly contains photoelectric converting and pre-amplifying circuits,LCD and keyset interface circuits and data storing circuits based on I2C bus. The circuits satisfy the system requirement:high precision,low power consumption,miniaturization and portability.The fifth chapter expatiate the soft design of the system. The interface of the sofyware is menu-styled. The components that deal with color and luminous density measurement,including standard input,system calibration,are emphasized.The sixth chapter analyses the experimental results and system precision. Most attention is paid to color and luminous density measurement,with color difference as a plus.Finally,the seventh chapter summarizes the word of the paper. The shortcoming is shown,and the direction of further modification and improvement is proposed.