JPS6431707U - - Google Patents

Description

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of the optical system of the device of the present invention, Figure 2 is a diagram showing the positional relationship between the divided corneal reflection images and the corresponding one-dimensional image sensor, and Figure 3 is the measurement position of the corneal reflection image of the subject's eye. 4 is an explanatory diagram of corneal curvature radius calculation, FIG. 5 is a block diagram of the signal processing system of the device of the present invention, FIG. 6 is a diagram showing the output of the one-dimensional image sensor, and FIG. A diagram showing the correspondence between the counter output S and the exaggeration coefficient K. Figure 8 is a diagram showing the anterior segment of the subject's eye and an exaggerated corneal shape display mixed together and displayed on the monitor. Figure 9 is a diagram showing the actual corneal reflection image. , Figures 10A and 10B are diagrams of exaggerated polygon graphs, Figure 10A is a diagram without irregular astigmatism, Figure 10B is a diagram with irregular astigmatism, and in the figures, 1 is a circular shape. slit, 1' is a corneal reflection image, 2 is an annular strobe, 3 is an annular lens, 4 is an aperture plate, 4a, 4d are circular apertures, 5 is an imaging lens, 6 is a dichroic mirror, 7 is a wedge prism,
9a to 9f are one-dimensional image sensors, 10 is a relay lens, 11 is an image pickup tube, 25 is an interface circuit, 26 is a microcomputer, 27 is a read-only memory, 35 is a graphic generator circuit, 40 is a waveform shaping circuit, 41 is a coparator, 46 is an up-down counter, 47 is a latch, 48 and 50 are up counters, 49 is a digital comparator, 51 is a PROM, and 53 is a peak position of the corneal reflection image.

Claims (1)

[Claims for Utility Model Registration] 1. An index whose index position in each meridian direction is on the same circumference is projected onto the eye to be examined, a corneal reflection image of the index is formed on a position detection sensor, and the image position in each meridian direction is A corneal shape measuring device that measures the shape of the cornea by detecting the corneal shape, comprising: a counting means for counting the sum of deviations of image positions in other meridian directions with respect to an image position in a predetermined meridian direction; When the image position is multiplied by _K2 in the meridian direction where the image position is the minimum using a predetermined exaggeration coefficient _K1 / _K2 , the image position is multiplied by _K1 in the meridian direction where the image position is the maximum to correct the axial asymmetry of corneal irregular astigmatism. What is claimed is: 1. A corneal shape measuring device comprising a calculation display means for calculating and displaying a polygonal figure with exaggerated characteristics. 2 When the output of the counting means is smaller than a first predetermined output, the exaggeration coefficient is set to 1, and when the output of the counting means is between the first predetermined output and a second predetermined output larger than the first predetermined output, the exaggeration coefficient is set to a first predetermined value larger than 1. The corneal shape measuring device according to claim 1, wherein the corneal shape measuring device is set to a second predetermined value smaller than the first predetermined value when the output is larger than the second predetermined value.