[OPTICAL REVIEW Vol. 18, No. 1 (2011) 153-156]
© 2011 The Japan Society of Applied Physics

Improved Measurement of Dynamic Modulation Transfer Functions on Display Using Pursuit Camera Method Based on Wavelet-denoising Method

Shau-Wei HSU, Chia-Ying CHANG, Zong-Ying CHUNG, and Kuei-Neng WU

Center for Measurement Standards, Industrial Technology Research Institute, Bldg. 16, 321, Sec. 2, Kuang Fu Rd, Hsinchu 300, Taiwan

(Received May 24, 2010; Revised September 29, 2010; Accepted November 12, 2010)

A new method was developed for studying dynamic modulation transfer functions (DMTFs) of liquid crystal display (LCD) based on the slanted edge method, improved wavelet-denoise (IWD) method, and Fourier transformation. Measurements were made for capturing the images of moving step-edge patterns on the display by a slightly tilted pursuit camera. The scanning-rate and contrast-dependent DMTFs of a LCD were demonstrated, and the corresponding parameters such as blurred edge width (BEW), spatial sharpness, and motion picture response time (MPRT) were calculated from the DMTF curves. A simple linear relationship between these parameters was found. The properties of a cathode ray tube (CRT) display were also measured for comparison with those of the LCD.

Key words: MTF, FPD, pursuit camera, wavelet, step edge