JPH10272101A - Ophthalmic equipment - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To suppress unnecessary light irradiation to an eye to be examined by changing the input light amount of a light receiving element that receives fundus reflection light of illumination light. A system control unit (50) rotates a disc slit (39) through a slit motor control circuit (57), and an opening and a light-shielding unit are made one-to-one by the rotation of the disc slit (39), and tracking light is emitted to the fundus oculi (Ea). The light amount is the fundus oculi Ea, with the time ratio of lighting on and off in the blinking cycle being 1: 1.
Flashing lighting. As a result, the amount of light per unit time does not decrease, so that the reflection luminance of the tracking light and the measurement light at the fundus oculi Ea does not decrease, and the irradiation time can be reduced without adversely affecting the visibility of the measurement indicator. It is possible to reduce the total exposure amount of laser light to the fundus oculi Ea of the eye E to be inspected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmic apparatus for examining biological information of a fundus region.

[0002]

2. Description of the Related Art Conventionally, a laser Doppler velocimeter that irradiates a moving object with laser light and measures the moving speed of the object from the frequency Doppler shift of the reflected light is generally known. A laser Doppler fundus blood flow meter applied to the measurement of blood flow velocity in blood vessels is disclosed in
No. 215150.

This fundus blood flow meter irradiates a measurement light beam onto a blood vessel in the fundus for a certain period of time to obtain a measurement value, but continues to accurately irradiate a measurement light beam to a measurement site due to the fixation of the eye to be examined. Since it is difficult, a tracking means is required to move the irradiation position of the measurement light beam on the measurement site in real time in response to the fixation fine movement after detecting the blood vessel position. This tracking system is based on
No. 503733, JP-A-7-155299, and the like. These irradiate the target blood vessel with tracking light in addition to the measurement light, and change the image receiving state of the reflected light to change the target blood vessel by fixation micromotion. In this method, the displacement is calculated and the measurement light is guided onto the target blood vessel.

That is, after performing an aiming operation for guiding tracking light onto a target blood vessel, a tracking operation is started. Before starting measurement, it is confirmed whether or not the measurement light beam is accurately tracked on the target blood vessel. In order to perform this, it is necessary to irradiate the measurement light beam on a trial basis.
In addition, it is necessary to perform AGC for adjusting the sensitivity of the light receiving element in order to make the S / N of a signal obtained by the light receiving element appropriate during tracking or measurement.

However, irradiation of the fundus with laser light
It is ideal to irradiate the laser light only during tracking or within the measurement time, because it adversely affects the living tissue in proportion to the intensity and the irradiation time. However, actually, it is important to perform aiming and tracking confirmation of the measurement light beam for accurate measurement, and a certain amount of time is required for setting conditions before measurement such as AGC.

[0006] Further, when the irradiation light amount is reduced in order to reduce the exposure amount of the laser light, the S / S of the signal obtained by the light receiving element is reduced.
Since N decreases and affects the accuracy of tracking and measurement, in a laser photocoagulation device or the like, the light amount of the treatment light is reduced during the position confirmation of the treatment light spot before performing treatment,
Means for suppressing the total exposure of laser light to the fundus are used.

[0007]

However, the above-described conventional laser Doppler fundus blood flow meter operates while viewing the fundus reflection image as a measurement indicator during aiming or beam confirmation. Complicated operations are required before measurement compared to the device. In addition, by applying the laser photocoagulation method to reduce the amount of laser light exposure by reducing the amount of tracking light or measurement light other than during tracking or measurement, measurement due to the decrease in reflection brightness at the fundus The operability is impaired due to the deterioration of the visibility of the indicator for use, and the examination time is prolonged as a whole, and as a result, the exposure amount of the laser beam to the subject's eye may increase. On the other hand, if the amount of light is reduced so as not to affect the visibility of the measurement indicator, the effect of suppressing the irradiation amount on the fundus cannot be expected.

Further, since the required amount of irradiation light is different due to differences in the reflectance of the fundus due to individual differences and parts, the light amount is determined in consideration of the worst case.
It is necessary to irradiate tracking light or measurement light with this light amount, and as a result, there is a possibility that many eyes are irradiated with an unnecessarily large amount of light.

An object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide an ophthalmologic apparatus in which an input light amount of a light receiving element for receiving fundus reflection light of illumination light is variable in order to suppress unnecessary light irradiation to an eye to be examined.

[0010]

To achieve the above object, an ophthalmic apparatus according to the present invention comprises: an irradiation optical system for irradiating a specific point on a fundus with illumination light; and a measurement apparatus for measuring predetermined information of the specific point. Means, measurement start means for operating the measurement means,
Blinking irradiation control means for blinking the illumination light before the measuring means starts operating.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiment. FIG. 1 shows a configuration diagram of a fundus blood flow meter according to an embodiment. A fundus illumination optical system from an observation light source 1 composed of a tungsten lamp or the like that emits white light to an objective lens 2 facing the eye E has a condenser lens. 3, for example, a field lens 4 with a band-pass filter that transmits only light in the yellow range, a ring slit 5 substantially conjugate to the pupil Ep of the eye E, a light-shielding member 6 substantially conjugate to the crystalline lens of the eye E,
Relay lens 7, transmissive liquid crystal plate 8, which is a fixation target display element movable along the optical path, relay lens 9, eye E to be examined
A light-shielding member 10, a perforated mirror 11,
Bandpass mirrors 12 that transmit light in the yellow range and almost reflect other light beams are sequentially arranged.

The ring slit 5, the light shielding members 6, 1
Numeral 0 is for separating the fundus illumination light and the fundus observation light in the anterior segment of the eye E, and its shape does not matter as long as it forms a necessary light-shielding region.

A fundus observation optical system is provided behind the perforated mirror 11, and includes a focusing lens 13, a relay lens 14, and a scale plate 1 movable along an optical path.
5. An optical path switching mirror 16 and an eyepiece 17 which can be inserted into and removed from the optical path are sequentially arranged to reach an examiner's eye e. On the optical path in the reflection direction when the optical path switching mirror 16 is inserted in the optical path, a television relay lens 18 and a CCD
A camera 19 is arranged, and an output of the CCD camera 19 is connected to a liquid crystal monitor 20.

An image rotator 21 is arranged on the optical path in the reflection direction of the band-pass mirror 12, and a galvanometric mirror 22 polished on both sides having a rotation axis perpendicular to the paper is arranged ahead of the image rotator 21. A focusing lens 23 movable along the optical path is arranged in the reflection direction of the surface 22a, and a lens 24 and a focus unit 25 movable along the optical path are arranged in the reflection direction of the upper reflection surface 22b. . The galvanometric mirror 22 is disposed on the front focal plane of the lens 24 having a conjugate relationship with the pupil Ep of the eye E to be inspected.

Behind the galvanometric mirror 22, an optical path length compensating meniscus 26, a black spot plate 27 having a light shielding portion in the optical path, and a concave mirror 28 are arranged concentrically on the optical path. A relay optical system is configured to guide a light beam that passes without being reflected by the lower reflecting surface 22a to the upper reflecting surface 22b of the galvanometric mirror 22. The meniscus 26 for correcting the optical path length is used to correct the vertical shift in the drawing caused at the positions of the upper reflecting surface 22b and the lower reflecting surface 22a due to the mirror thickness of the galvanometric mirror 22. It acts only in the optical path to 21.

In the focus unit 25, a dichroic mirror 29 and a condenser lens 30 are arranged on the same optical path as the lens 24, and a mask 31 and a mirror 32 are arranged on an optical path in the reflection direction of the dichroic mirror 29. The focus unit 25 can be integrally moved in a direction indicated by an arrow.

On the optical path in the incident direction of the condenser lens 30,
A fixed mirror 33 and an optical path switching mirror 34 that can be retracted from the optical path are arranged in parallel. On the optical path in the incident direction of the optical path switching mirror 34, a collimator lens 35 and a laser diode 3 for measurement that emits coherent red light, for example.
6 are arranged. Further, on the optical path in the incident direction of the mirror 32, a beam expander 37 composed of a cylindrical lens or the like, an opening and a light-shielding portion are in a one-to-one relationship as shown in FIG.
9. N which is composed of a plurality of ND filters and can be inserted into and removed from the optical path
A D filter group 40 and a tracking light source 41 that emits, for example, green light different from other high-luminance light sources are sequentially arranged.

On the optical path behind the focusing lens 23, a dichroic mirror 42, a field lens 4
3. A magnifying lens 44 and a one-dimensional CCD 45 with an image intensifier are sequentially arranged to form a blood vessel detection system.

On the optical path in the reflection direction of the dichroic mirror 42, an imaging lens 46, a confocal stop 47, and mirror pairs 48a and 48b substantially conjugate to the pupil Ep of the eye E to be examined are considered. Photomultipliers 49a and 49b are arranged in the reflection direction of 48b, respectively, and constitute a light receiving optical system for measurement. Although all the optical paths are shown on the same plane for the sake of illustration, the optical path from the laser diode 36 to the mask 31, the measuring optical path in the emission direction of the tracking light source 41, the mirror pair 48a,
Each of the reflected light paths 48b is orthogonal to the paper surface.

Further, a system control unit 50 for controlling the entire apparatus is provided. The system control unit 50 includes a one-dimensional CCD 45, photomultipliers 49a and 49b,
The outputs of the input means 51 operated by the examiner are respectively connected. The output of the system control unit 50 includes an optical path switching mirror 34, a laser diode 36, a tracking light source 41, a galvanometric mirror control circuit 52 for controlling the galvanometric mirror 22, a one-dimensional CCD.
45, a CCD sensitivity control circuit 53 for adjusting the light reception sensitivity, a photomultiplier sensitivity control circuit 54 for adjusting the light reception sensitivity of the photomultipliers 49a and 49b, a laser diode light emission control circuit 55 for controlling the light emission of the laser diode 36, an ND filter The ND filter driving means 56 for driving the group 40 and the motor control circuit 57 for driving the motor 38 are connected to each other. The output of the one-dimensional CCD 45 is connected to the galvanometric mirror control circuit 52 via a blood vessel position detection circuit 58.

FIG. 3 shows the arrangement of each light beam on the pupil Ep of the eye E to be examined. I denotes an area of the ring slit 5 illuminated by yellow illumination light, O denotes a fundus observation light beam and a perforated mirror 1.
1 is an image of an opening, V is a measurement / vessel received light beam, an image of an effective portion of the upper and lower reflection surfaces 22b and 22a of the galvanometric mirror 22, Da and Db are two measured light beams and two mirrors 48a and 48b, respectively. It is a statue. Further, P1 and P1 ′ are the incident positions of the measurement light, and indicate the positions of the measurement light selected by switching the optical path switching mirror 34, and the area M indicated by the dashed line is the lower reflection surface 22 of the galvanometric mirror 22.
It is an image of a.

The white light emitted from the observation light source 1 passes through the condenser lens 3, and only the yellow wavelength light is transmitted by the field lens 4 with the band pass filter, passes through the ring slit 5, the light shielding member 6, the relay lens 7, The transmissive liquid crystal 8 is illuminated from behind, passes through a relay lens 9 and a light blocking member 10, is reflected by a perforated mirror 11, and only light in the yellow range passes through a bandpass mirror 12, passes through the objective lens 2, and is illuminated. Once formed as a fundus illumination light beam image I on the pupil Ep of the optometry E, the fundus oculi Ea is illuminated almost uniformly. At this time, a fixation target is displayed on the transmissive liquid crystal plate 8, projected onto the fundus oculi of the eye E by illumination light, and presented to the eye E as a target image.

The reflected light from the fundus oculi Ea returns along the same optical path, is taken out of the pupil Ep as a fundus oculi observation light beam O, and the opening at the center of the perforated mirror 11 and the focusing lens 1
3. Pass the relay lens 14 and the fundus image on the scale 15
After forming an image as Ea ′, the light reaches the optical path switching mirror 16. Here, when the optical path switching mirror 16 is retracted from the optical path, the fundus oculi image Ea 'can be observed by the examiner's eye e via the eyepiece 17, while the optical path switching mirror 1
When the lens 6 is inserted in the optical path, the fundus image Ea ′ formed on the scale plate 15 is re-imaged on the CCD camera 19 by the television relay lens 18 and displayed on the liquid crystal monitor 20.

The apparatus is aligned with the eyepiece 17 or the liquid crystal monitor 20 while observing the fundus image Ea '. At this time, it is preferable to use an appropriate observation method according to the purpose. In the case of observation with the eyepiece 17, since the resolution is generally higher and the sensitivity is higher than that of the liquid crystal monitor 20, etc. It is suitable for reading and diagnosing minute changes. On the other hand, in the case of observation using the liquid crystal monitor 20, since the field of view is not restricted, the fatigue of the examiner can be reduced, and the output of the CCD camera 19 can be connected to an external video tape recorder, video printer, etc. Since it is possible to sequentially and electronically record changes in the measurement site on the image Ea ', it is extremely effective clinically.

Next, when the measuring laser diode 36 and the tracking light source 41 are turned on, the measuring light emitted from the laser diode 36 is collimated by the collimator lens 35, and when the optical path switching mirror 34 is inserted in the optical path. Are reflected by the optical path switching mirror 34 and the fixed mirror 33, respectively, and pass below the condenser lens 30. When the optical path switching mirror 34 is retracted from the optical path, they pass directly above the condenser lens 30. , Through the dichroic mirror 29.

On the other hand, the tracking light emitted from the tracking light source 41 is adjusted in light quantity by the ND filter group 40, becomes blinking light in the disc slit 39, and the beam diameter is expanded by the beam expander 37 at different magnifications in the vertical and horizontal directions. After being reflected at 32, the shaping mask 3
The dichroic mirror 29 is shaped into a desired shape by
The measurement light reflected by the light source and imaged in a spot shape at a position conjugate with the center of the opening of the mask 31;
Are superimposed. The superimposed measurement light and tracking light pass through the lens 24, are reflected once by the upper reflection surface 22b of the galvanometric mirror 22, pass through the black point plate 27, are reflected by the concave mirror 28, and are again returned to the black point plate 27 for optical path length correction. The light is returned to the galvanometric mirror 22 through the meniscus 26.

Here, the upper reflecting surface 22b and the lower reflecting surface 22a of the galvanometric mirror 22 are imaged at -1 times by the function of the relay optical system including the concave mirror 28, the black spot plate 27, and the meniscus plate 26 for correcting the optical path length. Therefore, by inserting / retreating the optical path switching mirror 34 into the optical path, the measurement light and the tracking light reflected at the positions P1 and P1 'on the back side of the image M of the galvanometric mirror 22 are converted to the galvanometric mirror. The light is returned to P2 and P2 ′ in the cutout portion 22 and goes to the image rotator 21 without being reflected by the galvanometric mirror 22. And
After passing through the image rotator 21, the bandpass mirror 12
The measurement light and the tracking light deflected by are irradiated to the fundus oculi Ea of the eye E through the objective lens 2.

As described above, the measuring light and the tracking light are reflected in the upper reflecting surface 22b of the galvanometric mirror 22, and when returning, enter the galvanometric mirror 22 in a state of being eccentric from the optical axis of the objective lens 2. Then, as shown in FIG. 3, the spot image P2 or P2 ′ on the pupil Ep.
After image formation, the fundus oculi Ea is illuminated like dots.

The scattered reflected light of the measurement light and the tracking light on the fundus oculi Ea is condensed again by the objective lens 2, reflected by the band-pass mirror 12, passes through the image rotator 21, and passes through the lower reflection surface 22a of the galvanometric mirror 22. The measurement light and the tracking light are separated by the dichroic mirror 42 through the focusing lens 23.

The tracking light is a dichroic mirror 4
2 through the field lens 43, and is imaged by the imaging lens 44 on the one-dimensional CCD 45 as a blood vessel image Ev 'which is larger than the fundus image Ea' by the fundus observation optical system, and a captured blood vessel image Based on Ev ', data representing the movement amount of the blood vessel image Ev' is created in the blood vessel position detection circuit 58 and output to the galvanometric mirror control circuit 52, and the galvanometric mirror control circuit 52 compensates for this movement amount. , The galvanometric mirror 22 is driven.

At this time, due to the spectral characteristics of the bandpass mirror 12, the illumination light from the observation light source 1
Thus, only the blood vessel image Ev 'by the tracking light is captured by the one-dimensional CCD 45. Also,
Since blood hemoglobin and melanin on pigment epithelium have significantly different spectral reflectances in the green wavelength region, the blood vessel image Ev 'can be captured with good contrast by setting the tracking light to green light.

On the other hand, the measuring light is a dichroic mirror 42
Are reflected by the mirrors 48a and 48b through the opening of the confocal stop 47, and are received by the photomultipliers 49a and 49b, respectively. The outputs of the photomultipliers 49a and 49b are output from the system controller 5 respectively.
0, and the light receiving signal is subjected to frequency analysis in the same manner as in the conventional example, and the blood flow velocity of the fundus oculi Ea is obtained.

Further, the fundus by measuring light and tracking light
Part of the scattered and reflected light at Ea is transmitted through the band-pass mirror 12 and guided to the fundus observation optical system behind the perforated mirror 11, and the tracking light forms an image as a bar-shaped indicator T on the scale plate 15. . At this time, the center of the indicator T is configured to be a conjugate point on the fundus oculi Ea with the tracking reference position initially set on the tracking sensor of the CCD camera 19.

FIG. 4 shows the eyepiece 17 or the liquid crystal monitor 20.
Shows a fundus image Ea ′, an optotype image F, and an indicator T, which are observed through the eye. At this time, a spot image of the measurement light (not shown) is observed superimposed on the center of the indicator T,
The indicator T can be moved one-dimensionally on the fundus oculi Ea by an operation member such as an operation rod of the input means 51. A perfect circle at the center of the field of view is a scale S called an aiming circle on the scale plate 15 and represents a range in which the indicator T can be moved.

The measurement is performed in the order of aiming, tracking start, tracking confirmation, and measurement start of the target blood vessel. The examiner first performs a fundus image Ea ′ before aiming the target blood vessel.
Focus. When the focus knob of the input means 51 is adjusted, the transmission type liquid crystal plate 8, the focusing lenses 13, 23, and the focus unit 25 are moved along the optical path in conjunction with the drive means (not shown). Thus, when the fundus image Ea 'is in focus, the transmissive liquid crystal plate 8, the scale plate 15, the one-dimensional CCD 45, and the confocal stop 47 are simultaneously conjugate with the fundus Ea.

After the focusing is completed, the examiner operates the input means 51 to move the optotype image F, guides the line of sight of the eye E, changes the observation area, and changes the blood vessel image E to be measured.
v ′ is moved into the circle S of the scale plate 15. Then, as shown in FIG. 5, the indicator T is rotated by operating the image rotator 21 with the operation rod of the input means 51 so that the indicator T is perpendicular to the traveling direction of the blood vessel Ev to be measured. . At this time, since the fundus oculi observation light does not pass through the image rotator 21, it is recognized that only the indicator T rotates.

Subsequently, by operating the operating rod of the input means 51, the indicator T, which is the tracking light, and the measured blood vessel Ev are aligned at right angles as shown in FIG. 6, and the indicator T is moved in the longitudinal direction. Then, a part of the indicator T is superimposed on the measured blood vessel image Ev 'in an orthogonal state.
At this time, the blood vessel image Ev ′ indicated and illuminated by the tracking light is applied to the elements of the one-dimensional CCD 45 of the blood vessel detection system arranged in the longitudinal direction of the tracking light as shown in FIG.
Are enlarged and imaged.

The reflection light of the tracking light projected on the fundus Ea passes through the image rotator 21 and the galvanometric mirror 22 and is projected onto the one-dimensional CCD 45 at -n times. Is stationary on the one-dimensional CCD 45 and the indicator T
Move in the longitudinal direction, only the blood vessel image Ev '
It will move on CD45.

During this time, the system controller 50 rotates the disk slit 39 via the slit motor control circuit 57 and the motor 38. Due to the rotation of the disc slit 39, the opening and the light-shielding portion become one-to-one, and the fundus oculi Ea of the tracking light
As shown in FIG. 8, the irradiation light amount changes to a one-to-one time ratio between lighting and extinguishing at the blinking period t.
Is half as compared with the continuous exposure.

The system control unit 50 is a one-dimensional CCD.
In response to the output of 45, the ND filter group 40 is appropriately moved in the optical path through the ND filter driving means 56, and is controlled so that the amount of tracking light to the fundus oculi Ea becomes the minimum necessary. At this time, the system control unit 50 determines the light amount only when the tracking light is turned on. The fact that the tracking light is turned on is determined by the output fluctuation of the one-dimensional CCD 45, the rotation synchronization signal from the motor 57, and the like. I can judge.

After the aiming of the target blood vessel is completed, the input means 51 is operated again to input a tracking start command to the system controller 50. When the output of the one-dimensional CCD 45 is received, the system controller 50 receives the final appropriate light amount. And drives the ND filter group 40. At the same time, the light receiving sensitivity of the one-dimensional CCD 45 is adjusted through the CCD sensitivity control circuit 53, and then, through the slit motor control circuit 57,
With the opening of the disk slit 39 reaching the optical path,
The motor 38 is stopped.

Next, when tracking is started, the moving amount x of the one-dimensional CCD 45 of the blood vessel image Ev 'shown in FIG. 7 from the reference position 45a is calculated in the blood vessel position detecting circuit 58 based on the light receiving signal of the one-dimensional CCD 45. Then, the galvanometric mirror control circuit 52 drives the galvanometric mirror 22 based on the movement amount x, and controls the image receiving position of the blood vessel image Ev ′ on the one-dimensional CCD 45 to reach the reference position 45a of the CCD 45. You.

Before or after the start of the tracking, the measuring light is irradiated so as to be superimposed on the tracking light in order to confirm the tracking state. In this embodiment, the beam spot U of the measurement light is positioned on the fundus oculi Ea as a reference equivalent position of the tracking light T so that the measurement blood vessel Ev can be accurately and easily captured by the tracking system, as shown in FIG. Irradiation is superimposed on 45a.

At this stage, the tracking is confirmed by the fact that the beam spot U of the measuring light is accurately irradiated on the target blood vessel Ev. If the tracking is not correctly performed, necessary correction work is performed. And the system control unit 5
0 drives the laser diode 36 via the laser diode emission control circuit 55 to make it blink. Thus, the irradiation light amount of the measurement light to the fundus oculi Ea changes as shown in FIG. 8 similarly to the case of the aiming, and the light exposure of the fundus oculi Ea is reduced by half compared with the continuous lighting.

The photomultipliers 49a, 49
b, the system control unit 50 transmits the laser diode 3 through the laser diode emission control circuit 55.
6 is controlled to control the amount of measurement light to the fundus oculi Ea to be the minimum necessary. At this time, the system control unit 50 determines the light amount only when the measurement light is on, and at the same time adjusts the light receiving sensitivity of the photomultipliers 49a and 49b through the photomultiplier sensitivity control circuit 54. The determination that the measurement light is on is made based on the output fluctuation of the photomultipliers 49a and 49b, the blinking cycle signal of the laser diode light emission control circuit 55, and the like. Further, if light receiving elements other than the photomultipliers 49a and 49b are provided in the light receiving optical system in order to detect the irradiation light amount of the measurement light, the consumption of the light receiving element for measurement can be reduced.

When the measurement is started by operating the input means 51 again after the tracking is confirmed, the system control unit 50 stops the blinking of the measurement light via the laser diode light emission control circuit 55 and performs a predetermined measurement. Do.

In the above description, the ratio of lighting and extinguishing when the measuring light flickers is set to 1: 1. However, turning on and off is performed by changing the size of the opening of the disc slit 39 and the control change of the laser diode light emission control circuit 55. If the ratio of light out is 1: 2, the fundus
The amount of exposure to Ea can be reduced to 1/3 of that during continuous lighting. In this way, by appropriately selecting the ratio of lighting and extinguishing, the exposure light amount of the fundus oculi Ea can be adjusted, and furthermore, such as slow blinking to draw further attention, apparently fast blinking such as continuous lighting, By appropriately changing the blinking frequency, it is possible to provide a work environment that is easy for the examiner to use.

[0048]

As described above, in the ophthalmologic apparatus according to the present invention, before the measurement means starts operating, the illumination light of the measurement indicator is illuminated in a blinking manner, so that the positioning and measurement site other than the measurement time can be performed. In the time for confirmation of, the exposure amount of the irradiation light of the measurement indicator to the fundus can be significantly reduced, and the optimal light amount can be used at the time of measurement, without impairing the visibility of the measurement indicator, There is no adverse effect on the operating environment. In addition, by adjusting the irradiation light amount synchronized with the blinking, it is possible to always secure an appropriate luminance, and since the light amount adjustment and the light receiving sensitivity adjustment can be performed with the light amount used for the measurement, the adjustment can be performed simply and accurately.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a fundus blood flow meter.

FIG. 2 is a front view of a disk slit.

FIG. 3 is an explanatory diagram of a light beam arrangement on a pupil.

FIG. 4 is an explanatory diagram of an examiner's field of view.

FIG. 5 is an explanatory diagram of an examiner's field of view.

FIG. 6 is an explanatory diagram of an examiner's field of view.

FIG. 7 is an enlarged front view of the one-dimensional CCD.

FIG. 8 is a time chart of the amounts of measurement light and tracking light.

FIG. 9 is an explanatory diagram of measurement light and tracking light.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Observation light source 19 CCD camera 20 Liquid crystal monitor 21 Image rotator 22 Galvanometric mirror 25 Focus unit 36 Laser diode 39 Disc slit 40 ND filter group 41 Tracking light source 45 One-dimensional CCD 49a, 49b Photomultiplier 50 System control circuit

Claims (8)

[Claims] An irradiation optical system for irradiating a specific point on the fundus with illumination light; a measuring unit for measuring predetermined information of the specific point; a measurement starting unit for operating the measuring unit; Ophthalmic equipment, comprising: blinking irradiation control means for blinking and irradiating the illumination light at a stage before the start of the operation. 2. The ophthalmologic apparatus according to claim 1, wherein the illumination light irradiation position moving means provided in the irradiation optical system, and the illumination light can be moved to the specific point by using the irradiation position moving means. . 3. The ophthalmologic apparatus according to claim 1, further comprising a measurement condition determination unit that determines a measurement condition of the measurement unit before the measurement unit starts operating. 4. The measurement condition determining means has first light receiving means for receiving the reflected light of the illumination light from the fundus, based on an output of the first light receiving means when the illumination light is turned on. The ophthalmologic apparatus according to claim 3, wherein the measurement condition is determined. 5. The light control device according to claim 4, further comprising a dimming unit that sets the measurement condition determined by the measurement condition determination unit as an incident light amount condition of the illumination light and changes the incident light amount of the illumination light based on the incident light amount condition. The ophthalmic device as described. 6. A second light receiving means for obtaining predetermined information of the specific point in the measuring means, wherein a measuring condition determined by the measuring condition determining means is a light receiving sensitivity condition of the second light receiving means, The ophthalmologic apparatus according to claim 4, further comprising a light receiving sensitivity control unit that changes the light receiving sensitivity of the second light receiving unit based on the light receiving sensitivity condition. 7. The ophthalmologic apparatus according to claim 6, wherein the first light receiving means and the second light receiving means are the same. 8. An image receiving unit for receiving a fundus image illuminated by the illumination light, and the irradiation position moving unit is driven based on information from the image receiving unit to irradiate the illumination light in the vicinity of the specific point. The ophthalmologic apparatus according to claim 2, further comprising a tracking unit that performs tracking.