JPH07178053A - Light scanning ophthalmology device - Google Patents

Abstract

PURPOSE:To photograph a minute eyeground image by converting the scanning phase or the scanning rate by a photographing mode. CONSTITUTION:The beam flux from a laser beam source 1 is radiated on the eyeground of an eye to be examined E passing through a beam dividing member 4, a polygon mirror 5, a galvanometric mirror 7, and the like, and the reflected beam or the excited fluorescence is returned in the same optical path, it is reflected by the beam dividing member 4, received by a photoelectric sensor 12 through a focus lens and the like, and the eyeground image is transcribed to a TV monitor 15 through a signal process control means. In this case, by making the vibration rate of the galvanometric mirror 7 at 1/2, the scanning lines are made two times, and a minute image can be photographed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning ophthalmologic apparatus used as an optometry apparatus in an ophthalmology clinic or the like.

[0002]

2. Description of the Related Art Imaging of an eye to be inspected includes reflection light imaging in which a light beam is irradiated onto the eye to be inspected and the reflected light thereof is received, and fluorescence imaging in which a fluorescent agent is intravenously injected into a subject to receive excited fluorescence. However, in the conventional optical scanning ophthalmologic apparatus, irrespective of this photographing mode, the light beam is always scanned under a constant scanning condition to perform photographing.

[0003]

However, in the above-mentioned conventional optical scanning ophthalmologic apparatus, for example, as in fluorescence photography, a fluorescence photograph of a fundus image that changes with time after intravenous injection of a fluorescent agent is taken, and further, a fundus blood vessel. In the case of enlarging and capturing the details of the above, it is not possible to take a sufficiently fine fundus photograph because the scanning conditions are constant. Further, if the number of scanning lines is increased, it is difficult to apply it to a fast moving object.

A first object of the present invention is to solve the above problems and provide an optical scanning ophthalmologic apparatus for obtaining a fundus image with little flicker without changing the number of screens.

A second object is to provide an optical scanning ophthalmologic apparatus capable of changing the scanning rate according to the photographing mode to enable fine photographing.

A third object is to provide an optical scanning ophthalmologic apparatus for changing the photographing angle of view according to the photographing mode and magnifying and photographing.

[0007]

An optical scanning ophthalmologic apparatus according to a first aspect of the present invention for achieving the above object comprises a main scanning means for scanning a light beam applied to an eye to be inspected and a direction perpendicular to the main scanning means. An optical scanning ophthalmologic apparatus comprising: a sub-scanning unit for scanning the main scanning unit and a control unit for interlacing the main scanning unit and the sub-scanning unit.

An optical scanning ophthalmologic apparatus according to a second aspect of the present invention is provided with an optical scanning ophthalmologic apparatus including main scanning means for scanning a light beam applied to an eye to be inspected and sub-scanning means for scanning in a direction perpendicular to the main scanning means. The scanning rate varying means is provided for varying the scanning rate of one of the main scanning means and the sub-scanning means with respect to the scanning rate of the other scanning means.

An optical scanning ophthalmologic apparatus according to a third aspect of the present invention comprises an optical scanning ophthalmologic apparatus including main scanning means for scanning a light beam applied to an eye to be examined and sub-scanning means for scanning in a direction perpendicular to the main scanning means. It is characterized in that it has an angle of view changing means for changing the angle of view by changing the scanning rate or the scanning width of the sub-scanning means.

[0010]

The optical scanning ophthalmologic apparatus of the first invention having the above-mentioned structure substantially increases the number of scanning lines to obtain a flicker-free fundus image.

In the optical scanning ophthalmologic apparatus of the second invention, the scanning rate of one scanning unit is changed by a predetermined amount with respect to the scanning rate of the other scanning unit, the number of scanning lines is increased, and the fundus photography or the like is performed in the fine mode. Take a picture.

Further, the optical scanning ophthalmologic apparatus of the third invention changes the scanning rate or the scanning width of the sub-scanning means to change the photographing angle of view, and magnifies and photographs the fundus and the like.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on the illustrated embodiments. FIG. 1 is a configuration diagram of the first embodiment, in which a confocal diaphragm 2, a focus lens 3, and a light splitting member 4 such as a half mirror or a perforated mirror are provided on an optical path from a laser light source 1 to an eye E to be inspected. A polygon mirror 5 that scans in the horizontal direction with respect to the optical axis, a concave mirror 6, a galvano mirror 7 that scans in the direction perpendicular to the optical axis, and a concave mirror 8 are sequentially arranged.

In the reflecting direction of the light splitting member 4, the plane mirror 9,
A focus lens 10, a confocal diaphragm 11, and a photoelectric sensor 12 such as a photomultiplier are arranged, and the output from the photoelectric sensor 12 has a mode selection button 13 for selecting a normal mode A or a fine mode B. Further, the output of the signal processing control means 14 is connected to the television monitor 15. Focus lenses 3 and 10
Are interlocked with each other and adjusted so that the confocal diaphragm 2 and the photoelectric sensor 12 are conjugated with the fundus Er. The reflecting surfaces of the polygon mirror 5 and the galvano mirror 7 are conjugate with the pupil Ep by the concave mirrors 6 and 8, respectively. Although the galvano mirror 7 is a plane mirror, it may be a concave mirror to have a light collecting function.

In the above-mentioned structure, the light beam from the laser light source 1 passes through the confocal diaphragm 2, the focus lens 3, the light splitting member 4, the polygon mirror 5, the concave mirror 6, the galvano mirror 7, and the concave mirror 8 to the eye E to be examined. Scan the fundus Er. The reflected light from the fundus Er or the fluorescence excited by the fundus Er is reflected by the returning light splitting member 4 along the same optical path, and is received by the photoelectric sensor 12 via the plane mirror 9, the focus lens 10, and the confocal diaphragm 11. The signal from the photoelectric sensor 12 is converted into a two-dimensional image signal by the signal processing control means 14, and the television monitor 1
The image of the fundus is projected on 5. At this time, the scanning of the galvanometer mirror 7 is performed at the frame rate, and the polygon mirror 5 is set to 1
Rotate according to the number of scanning lines in the frame.

FIG. 2 shows scanning lines, (a) shows a normal mode A
, And (b) shows the scanning line in the fine mode B in which the number is doubled. Set the vibration rate of galvanometer mirror 7 to 1
When it is set to / 2, the number of scanning lines is doubled, and the fine mode B can be set. In this case, the frame rate is also halved, but in the case of reflected light photography that does not change with time, there is almost no problem even if the frame rate is reduced. In order to keep the frame rate constant and capture a fine image, the rotation speed of the polygon mirror 5 may be doubled.

FIG. 3 shows scanning lines according to an interlaced scanning system, that is, an interlaced scanning system different from the first embodiment,
Internal scanning is performed between the normal scanning rasters of FIG. 2 (a).
The raster of (b) is alternately scanned to form one frame by two field scans. Therefore, the frame rate is halved. In order to perform such interlaced scanning, the scanning rates of the polygon mirror 5 and the galvano mirror 7 may be shifted by half the time for one scanning line, so that in the next scanning, the scanning speed of the previous scanning line is always set. Flickering becomes less noticeable.

The horizontal resolution can be further increased by changing the sampling rate of the signal from the photoelectric sensor 12 according to the normal photographing or the fine photographing, and increasing the number of pixels at the double rate in the fine mode. Further, in the case of fluorescence photography, since it is necessary to photograph the change with time, generally, the photographing is performed in the normal mode, but when there is no change with time so quickly, the fine mode may be photographed. Further, the fine mode shooting is more effective when shooting a wide fundus range.

FIG. 4 shows a second embodiment, and the configuration of the optical system is the same as that of FIG. 1 and enables variable magnification photographing. The output of the photoelectric sensor 12 is a signal processing control means 17 having an angle of view selection button 16 capable of selecting a 40 ° angle of view C and a 20 ° angle of view D.
And is connected to the TV monitor 15.

An angle of view of 40 ° is displayed on the television monitor 15 shown in FIG. 4, and 20 ° is shown on the television monitor 15 of FIG.
An enlarged image of the angle of view of is displayed. To change the angle of view, do not change the rotation of the polygon mirror 5 for horizontal scanning,
Either one of the vibration rate and the amplitude of the galvanometer mirror 7 for vertical scanning is changed to 1/2, and the photoelectric sensor 12
The signal acquisition time from is halved. That is, the angle of view is 40 °
One half of the time signal is taken in for one horizontal scanning time.

In order to maintain the number of horizontal pixels, the sampling rate is doubled, and when displaying on the TV monitor 15, the signal is doubled in time and output so as to match the horizontal scanning time of the TV monitor 15. This allows
Even when the angle of view is set to 20 °, the frame rate, the number of scanning lines, and the horizontal resolution are kept constant, but the scanning line density and the horizontal pixel density are doubled on the subject surface.
It is possible to project even finer parts.

Further, if the sampling rate is set high from the beginning, it is not always necessary to change it, and if such conversion is continuously performed, it is possible to continuously change the object like a zoom lens. is there.

[0023]

As described above, in the optical scanning ophthalmologic apparatus according to the first invention, the flicker becomes inconspicuous due to the interlaced scanning.

The optical scanning ophthalmologic apparatus according to the second invention is
By changing one scanning rate of the scanning means to the other and switching to the fine mode, it is possible to take an image with high diagnostic value.

Further, the optical scanning ophthalmologic apparatus according to the third invention is
By changing the scanning rate or the scanning width of the sub-scanning unit to change the angle of view, it is possible to perform magnified imaging, and it is possible to capture an image with high resolution and a large amount of diagnostic information.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment.

FIG. 2 is an explanatory diagram of scanning lines.

FIG. 3 is an explanatory diagram of scanning lines.

FIG. 4 is a configuration diagram of a second embodiment.

FIG. 5 is an explanatory diagram of an enlarged fundus image.

[Explanation of symbols]

 1 Laser Light Source 3, 10 Focus Lens 5 Polygon Mirror 7 Galvano Mirror 12 Photoelectric Sensor 14, 17 Signal Processing Control Means 15 TV Monitor

Claims (3)

[Claims] 1. An optical scanning ophthalmologic apparatus comprising: a main scanning means for scanning a light beam applied to an eye to be inspected; and a sub-scanning means for scanning in a direction perpendicular to the main scanning means. An optical scanning ophthalmologic apparatus, characterized in that it has control means for causing sub-scanning means to perform interlaced scanning. 2. An optical scanning ophthalmologic apparatus comprising: a main scanning unit that scans a light beam applied to an eye to be inspected; and a sub-scanning unit that scans in a direction perpendicular to the main scanning unit. The scanning rate of one of the sub-scanning means is
An optical scanning ophthalmologic apparatus having a scanning rate changing means for changing the scanning rate of the other scanning means. 3. An optical scanning ophthalmologic apparatus comprising: a main scanning unit that scans a light beam applied to an eye to be inspected; and a sub-scanning unit that scans in a direction perpendicular to the main scanning unit. An optical scanning ophthalmologic apparatus comprising an angle-of-view changing means for changing a field rate by changing a scanning rate or a scanning width.