[OPTICAL REVIEW Vol. 2, No. 5 (1995) 388-393]

Topographic Analysis of Ocular Fundus Using the Fourier Transform Method for Projected Grating Images

Takeaki YOSHIMURA,1 Nobuaki KOHINATA,1 Hajime NAKATANI2 and Norihito SUZUKI3

1Department of Computer and Systems Engineering, Faculty of Engineering, Kobe University, Rokko, Nada, Kobe, 657 Japan, 2Seitoku Memorial Hospital, Ayazono, Takaishi, Osaka, 592 Japan, 3Department of Precision Engineering, Osaka Electro-Communication University, Hatsumachi, Nayagawa, Osaka, 572 Japan

(Received March 8, 1995; Accepted July 24, 1995)

In topography measurements of a local ocular fundus of the human eye using a grating-pattern projection technique, a pre-processing method to detect fringes accurately and a generalized Fourier transform method to analyze the fringe deformations are proposed. The method of analysis compensates for fringe deformations caused by instrumental characteristics. By combining the two methods, depth information can be determined with high accuracy. It is shown that the topographic parameters of the optic disc and the fundus slopes in the rim area are obtained with good reproducibility.

Key words : topography, Fourier transform method, pattern projection, glaucoma, ocular fundus