WO2018203562A1

WO2018203562A1 - Slit lamp microscope

Info

Publication number: WO2018203562A1
Application number: PCT/JP2018/017455
Authority: WO
Inventors: 清水　仁
Original assignee: 株式会社トプコン
Priority date: 2017-05-02
Filing date: 2018-05-01
Publication date: 2018-11-08
Also published as: JP6904776B2; JP2018187064A

Abstract

[Problem] To provide a slit lamp microscope capable of improving test precision without burdening a subject. [Solution] A slit lamp microscope comprising: an illumination system that has a light source for outputting illumination light, and shines, upon a subject eye, observation light of limited area by passing the illumination light through a beam controlling part, the area of an opening of which can be altered; an observational system for observing observation light returning from the subject eye; and a control unit for controlling at least the operation of the illumination system; the microscope comprising a slit opening area detector for detecting the area of the opening; and the control unit controlling the intensity of the light source on the basis of the opening area detected by the opening area detector.

Description

Slit lamp microscope

The present invention relates to an improvement of a slit lamp microscope.

Generally, a slit lamp microscope is widely used for ophthalmic examination as an ophthalmic apparatus that acquires an image of a cross-section of the cornea by cutting a light section of the cornea using slit light.

As disclosed in Patent Document 1, such a conventional slit lamp microscope has a light source that outputs illumination light, and has a pair of slit blades in which the arrangement interval of illumination light output from the light source is variable. An illumination system that irradiates the subject's eye with slit light having an arbitrary width formed through the slit portion, an observation system that guides the return light of the slit light from the subject's eye to the imaging device, and the illumination system and the observation system And a controller for controlling the operation of the apparatus.

When observing and diagnosing the eye to be inspected using such a slit lamp microscope, the cornea is irradiated with slit light to observe the cornea, but more detailed observation is required depending on the circumstances. In some cases, it may be required to illuminate the cornea with high illuminance.

In this case, a part of the light irradiated to the cornea is reflected by the cornea, but most of the light passes through the cornea and reaches the fundus. Therefore, when the cornea is illuminated with high illuminance, The safety value for light damage to the camera may be exceeded.

Therefore, conventionally, there has been a demand for a slit lamp microscope that can improve observation accuracy without imposing a burden on the subject.
Patent Publication No. 2014-108339

The present invention is to solve such a conventional problem, and the problem is to provide a slit lamp microscope that can improve observation accuracy without imposing a burden on a subject. .

In order to achieve the above object, according to the first aspect of the present invention, the slit lamp microscope has a detecting means for detecting the condition of the illumination system, and controls the luminous intensity of the illumination light source based on the detection result of the detecting means. It is characterized by doing.
The invention according to claim 2 is characterized in that the condition of the illumination system is a light amount of a light source.

According to a third aspect of the present invention, there is provided a light source that outputs illumination light, and the illumination light is subjected to observation light whose area is limited by passing through a light beam control unit capable of changing the area of the opening. A slit lamp microscope comprising: an illumination system that irradiates an optometry; an observation system that observes return light of the observation light from the eye to be examined; and a control unit that controls at least the operation of the illumination system. An opening area detecting unit for detecting the area of the light source, and the control unit controls the luminous intensity of the light source based on the opening area detected by the opening area detecting unit.

According to a fourth aspect of the present invention, the light flux control unit has a slit portion, and the slit portion has at least a pair of slit blades whose arrangement interval is variable, and is formed so that the interval between the slit blades can be detected. It is characterized by being.

According to a fifth aspect of the present invention, the light flux control unit has a field stop, and a plurality of apertures having different diameters are selectively disposed on the optical axis to thereby reduce the diameter of the light flux passing through the aperture. It is variable and formed so that the arranged opening can be detected.

In the invention of claim 6, the light beam control unit includes a slit portion and a field stop portion provided on the side opposite to the light source of the slit portion, and the field stop portion is Formed by a disc-shaped turret rotatably arranged in an orthogonal direction, and the opening comprises a plurality of circular openings arranged concentrically in the turret body and a single curved teardrop-shaped opening, The curved teardrop-shaped opening includes a large-diameter arc end, a small-diameter arc end disposed concentrically facing the large-diameter arc end, and the small-diameter end from the large-diameter arc end. A curved contour portion formed such that the width dimension gradually decreases toward the arc end, and the curved teardrop-shaped opening can continuously change and control the width of the light beam that has passed through the slit portion. It is characterized by.

According to the seventh aspect of the present invention, when the arrangement interval between the pair of slit blades of the slit portion and the opening diameter of the field stop portion are set by the examiner, the control unit detects the opening area. A maximum luminous intensity value of the light source is determined based on an arrangement interval of the pair of slit blades detected by the unit and an aperture diameter of the field stop, and the luminous intensity value of the light source is set to be equal to or less than the maximum luminous intensity value. It is comprised by these.

In the invention according to claim 8, the control unit has a storage unit, the storage unit is an opening area consisting of the set interval width of the pair of slit blades and the aperture diameter of the field stop unit, The maximum luminous intensity value of an appropriate light source that does not exceed the fundus illuminance safety value even when the observation light corresponding to the arrangement interval of the pair of slit blades and the opening diameter of the field stop is irradiated on the fundus of the eye to be examined. The control unit refers to the data in the storage unit, and refers to the data in the storage unit based on the slit width of the slit unit detected by the aperture area detection unit and the aperture diameter of the field stop unit. It is characterized by determining a maximum luminous intensity value.

The invention according to claim 9 is characterized in that the opening area detection unit acquires the slit width value by detecting an operation amount of the slit operation unit.
The invention according to claim 10 is characterized in that the opening area detector detects a slit width value by detecting a movement amount of the pair of slit blades.
The invention according to claim 11 is characterized in that the opening area detector detects an opening area based on an opening image of an anterior ocular segment image acquired by an imaging device arranged in an observation system.

The invention according to claim 12 is characterized in that the opening area detecting unit detects an opening diameter formed by the opening of the turret by measuring a step of a stepping motor that drives the turret. To do.
The invention according to claim 13 is characterized in that the opening area detecting means detects an opening diameter by detecting a rotation angle of the turret by means of a light detection unit.

Conventionally, in the slit lamp microscope, the light intensity of the light source was controlled only by the voltage level, but the illuminance on the cornea and the illuminance on the fundus were different due to individual differences in the light source and slight positional deviation during installation. Even if the luminous intensity of the light source is adjusted so that it does not exceed the safe fundus illuminance value at the time of shipment from the factory under the worst conditions with respect to the fundus of the subject with the slit part and field stop part opened. When the user replaces the light source, the adjustment in relation to the fundus illuminance value cannot be performed after the replacement.Therefore, the safety value of the fundus illuminance may be exceeded or sufficient illuminance may not be obtained. It was.

However, in the first and second aspects of the invention, the light intensity of the illumination light source is controlled on the basis of the detection result of the detection means. Since it is configured to control the light intensity by monitoring the light amount of the light source instead of controlling by voltage etc., it is effective for situations where the safety value of fundus illuminance exceeds the safe value due to light source deterioration or light source replacement It becomes possible to prevent.

In addition, since the maximum luminous intensity of the light source has been uniformly limited so as to keep the fundus illuminance below a safe value under all conditions, for example, even when the fundus illuminance reaches a safe value by narrowing the slit width, There was a problem that the luminous intensity could not be increased and the observation site could not be observed in more detail.

However, in the inventions according to claims 3 to 13, an opening area detection unit that detects the area of the opening is provided, and the control unit is configured to detect a light source based on the opening area detected by the opening area detection unit. Since it is configured to control the luminous intensity, the maximum luminous intensity can be made variable corresponding to the opening area set by the slit part and the field stop part. Within the range of the maximum luminous intensity, the luminous intensity of the light source can be freely increased, and more precise observation can be performed while eliminating the possibility of optical damage to the eye to be examined.

It is a conceptual diagram which shows the whole structure of the slit lamp microscope which concerns on one embodiment of this invention. It is a conceptual diagram which shows the whole structure of the slit lamp microscope which concerns on one embodiment of this invention. It is a conceptual diagram which shows the structure of the field stop part with which the slit lamp microscope which concerns on one embodiment of this invention is equipped. It is a conceptual diagram which shows the structure of the field stop part with which the slit lamp microscope which concerns on one embodiment of this invention is equipped. 1 is a block diagram showing an overall configuration of a slit lamp microscope according to an embodiment of the present invention. It is a figure which shows the flowchart in the case of performing the luminous intensity control of a light source based on the set slit width and field stop diameter in the slit lamp microscope which concerns on one embodiment of this invention.

Hereinafter, a slit lamp microscope according to the present invention will be described in detail based on embodiments shown in the accompanying drawings.

In the apparatus optical system according to the present embodiment, the direction from the lens (objective lens) located closest to the subject to the subject is defined as the forward direction, and the opposite direction is defined as the backward direction. The horizontal direction orthogonal to the front direction is the left-right direction. The direction perpendicular to both the front-rear direction and the left-right direction is defined as the up-down direction. The description will be made on the assumption of the above definition of direction.

[overall structure]
The overall configuration of the slit lamp microscope according to the present embodiment will be described with reference to FIGS. 1 and 2. A computer 100 is connected to the slit lamp microscope 1. The computer 100 performs various control processes and arithmetic processes.

In addition, instead of providing the computer 100 separately from the microscope main body (housing for storing the optical system or the like), a configuration in which the same computer is mounted on the microscope main body can be applied.

The slit lamp microscope 1 is placed on the table 2. The computer 100 may be installed on another table or in another place. The base 4 is configured to be movable in the horizontal direction via the moving mechanism unit 3. The base 4 is moved by tilting the operation handle 5. The support portion 15 is moved up and down with respect to the base 4 by rotating the operation handle 5 around the axis.

A support portion 15 that supports the observation system 6 and the illumination system 8 is provided on the upper surface of the base 4. Further, in the present embodiment, the support unit 15 supports the background illumination system 20 shown in FIG.

A support arm 16 that supports the observation system 6 is attached to the support unit 15 so as to be rotatable in the left-right direction. A support arm 17 that supports the illumination system 8 and the background illumination system 20 is attached to the upper portion of the support arm 16 so as to be rotatable in the left-right direction. The

support arms

16 and 17 are independently coaxially rotatable.

The observation system 6 is moved by manually rotating the support arm 16. The illumination system 8 and the background illumination system 20 are moved by manually rotating the support arm 17.

Note that each of the

support arms

16 and 17 may be configured to be rotated by an electric mechanism. In that case, an actuator for generating a driving force for rotating the

support arms

16 and 17 and a transmission mechanism for transmitting the driving force are provided. The actuator is constituted by, for example, a stepping motor (pulse motor). The transmission mechanism is constituted by, for example, a combination of gears, a rack and pinion, or the like.

The illumination system 8 irradiates the eye E with illumination light. As described above, the illumination system 8 can turn in the left-right direction around the rotation axis. Thereby, the irradiation direction of the illumination light to the eye E is changed. The illumination system 8 may be configured to turn in the vertical direction, or may be configured to change the elevation angle and depression angle of the illumination light.

The intensity of the illumination light is changed using the illumination intensity operation unit 18 provided on the base 4. Note that the intensity of the background illumination light applied to the eye E by the background illumination system 20 may also be configured to be performed using the illumination intensity operation unit 18.
It is also possible to change the intensity of the illumination light or the background illumination light so that it can be changed by another operation member. As other operation members, there are an operation member provided in the housing of the slit lamp microscope 1 and an operation member provided in the computer 100.

The observation system 6 has a pair of left and right optical systems that guide reflected light from the eye E to be examined with illumination light (and background illumination light). This optical system is housed in the barrel main body 9. The end of the lens barrel body 9 is an eyepiece 9a. The examiner looks at the eye E with the naked eye by looking into the eyepiece 9a.

As described above, the lens barrel body 9 can be rotated in the left-right direction by rotating the support arm 16. Thereby, the direction of the observation system 6 with respect to the eye E can be changed.
The reflected light of the illumination light includes various types of light that pass through the eye E such as scattered light, for example, and these various types of light are referred to as “reflected light”.

A chin rest 10 is disposed at a position facing the lens barrel body 9. The chin rest 10 is provided with a chin rest 10a and a forehead rest 10b for stably arranging the face of the subject.

An observation magnification operation knob 11 for changing the observation magnification is disposed on the side surface of the barrel main body 9. Further, an imaging device 13 for photographing the eye E is connected to the barrel main body 9.
The imaging device 13 includes an imaging element.
The imaging element is a photoelectric conversion element that detects light and outputs an electrical signal (image signal). The image signal is input to the computer 100. As the imaging element, for example, a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor is used. A mirror 12 that reflects the illumination light beam output from the illumination system 8 toward the eye E is disposed below the illumination system 8. The mirror 12 reflects the background illumination light output from the background illumination system 20 toward the eye E.

[Configuration of optical system]
The configuration of the optical system of the slit lamp microscope 1 will be described with reference to FIG. The slit lamp microscope 1 includes an observation system 6, an illumination system 8, and a background illumination system 20.

[Observation system]
The observation system 6 includes a pair of left and right optical systems. The left and right optical systems have substantially the same configuration. The operator can observe the eye E to be examined with binocular eyes using the left and right optical systems. In FIG. 2, only one of the left and right optical systems of the observation system 6 is shown. Reference numeral O <b> 1 is an optical axis (observation optical axis) of the observation system 6.

Each of the left and right optical systems of the observation system 6 includes an objective lens 31, a variable magnification optical system 32, a diaphragm 33, an imaging lens 35, a prism unit 36, and an eyepiece lens 37. The beam splitter 34 is provided in one or both of the left and right optical systems. The eyepiece lens 37 is provided in the pier portion 9a. A symbol P indicates a position where an image of the observation site is formed by the imaging lens 35. This image is observed through the eyepiece lens 37. Reference sign Ec represents the cornea of the eye E, reference sign Ep represents the iris, and reference sign Er represents the fundus. Reference Eo indicates the examiner's eye.

The variable magnification optical system 32 includes a plurality of (for example, two)

variable magnification lenses

32a and 32b. In this embodiment, a plurality of variable power lens groups that can be selectively inserted into the optical path of the observation system 6 are provided.
These variable power lens groups are configured to give different magnifications. A variable power lens group disposed in the optical path of the observation system 6 is used as the

variable power lenses

32a and 32b. Thereby, the magnification (field angle) of an observation image or a captured image of the eye E to be examined can be changed. Changing the magnification, that is, switching the zoom lens group disposed in the optical path of the observation system 6 is performed by operating the observation magnification operation knob 11. Moreover, you may comprise so that a magnification may be electrically changed using a switch etc. which are not illustrated.

The beam splitter 34 divides the light traveling along the observation optical axis O1 into two. The light transmitted through the beam splitter 34 is guided to the examiner's eye Eo through the imaging lens 35, the prism unit 36, and the eyepiece lens 37. The prism unit 36 includes two

optical elements

36a and 36b. The prism unit 36 can invert the image and change the width of the left and right observation optical axes according to the eye width of the examiner.

On the other hand, the light reflected by the beam splitter 34 is guided to the imaging element 43 of the imaging device 13 via the relay lens 41 and the mirror 42. The image sensor 43 detects the reflected light and generates an image signal.

[Lighting system]
The illumination system 8 includes a light source 51, a relay lens 52, an illumination stop 56, a condenser lens 53, a slit portion 54, a field stop portion 60, and an imaging lens 55. A symbol O2 indicates the optical axis of the illumination system 8 (illumination optical axis).

The light source 51 outputs illumination light. Note that a plurality of light sources may be provided in the illumination system 8. For example, both a light source (halogen lamp, LED, etc.) that outputs steady light and a light source (xenon lamp, LED, etc.) that outputs flash light can be provided as the light source 51. Further, a light source for corneal observation and a light source for fundus observation may be provided separately. The light source 51 includes at least a visible light source that outputs visible light. The light intensity can be changed according to the magnitude of the power applied to the light source 51.

(Flux control part)
In the present embodiment, the illumination system 8 has the light beam control unit 70 that can change the area of the opening 71 through which the illumination light of the light source 51 passes, and the area by passing through the light beam control unit 70. The eye E is irradiated with observation light that is limited.

That is, in the present embodiment, the light beam control unit 70 detects the area of the slit 54, the field stop 60, and the area of the opening 71 formed by the slit 54 and the field stop 60. The control unit 101 controls the light intensity of the light source 51 based on the opening area detected by the opening area detection unit.

<Slit part>
The slit portion 54 is used for generating slit light (observation light). The slit portion 54 has a pair of

slit blades

54a and 54b disposed to face each other at a predetermined interval. By changing the arrangement interval (slit width) of the

slit blades

54a and 54b, the width of the slit light is changed. The interval between the

slit blades

54a and 54b can be arbitrarily adjusted by manual operation. In this case, you may comprise so that the

slit blades

54a and 54b may be electrically opened and closed.

<Field stop>
As shown in FIGS. 2, 3, and 4, the field stop 60 is disposed adjacent to the slit 54 on the side opposite to the light source 51 of the slit 54 and has a plurality of openings 62 having different sizes and shapes. And a turret 61 that rotates about the rotation center 66.

As shown in FIGS. 3 and 4, in the present embodiment, the turret 61 is a disk-like member that is rotatably arranged in a direction orthogonal to the illumination optical axis 02, and the opening 62 is It consists of four

circular openings

63a, 63b, 63c, 63d and a single curved teardrop-shaped opening 64 arranged concentrically. The

circular openings

63a, 63b, 63c, and 63d are formed to have different diameters, and are arranged so that the centers of the openings are equally spaced from each other so that the diameter gradually increases in the clockwise direction.
Therefore, it is possible to appropriately limit the illumination range of the observation surface by appropriately rotating the turret 61 to align the center of the arbitrary opening 62 with the illumination optical axis 02.

When the smallest circular opening 63a is arranged on the illumination optical axis 02, it is possible to form aperture light having the smallest diameter than the diameter of the illumination light beam 65, and the largest circular opening 63d serves as the illumination optical axis 02. When arranged on the top, it is possible to form aperture light having the same maximum diameter as that of the illumination light beam 65.

The curved teardrop-shaped opening 64 includes a large-diameter arc end portion 64a, a small-diameter arc end portion 64b arranged concentrically facing the large-diameter arc end portion 64a, and the large-diameter arc end portion. The curved teardrop-shaped openings 64 are formed by

curved contour portions

64c and 64d formed so that the width dimension gradually decreases from the end portion 64a to the small-diameter arc end portion 64b, as shown in FIG. The width of the light beam that has passed through the slit portion 54 can be continuously changed and controlled.

As shown in FIG. 3, the turret 61 is disposed with the centers of the plurality of openings 62 aligned with the illumination optical axis 02, and the examiner rotates the turret 61 appropriately to open the desired opening 62. By selectively disposing the portion 54 with respect to the illumination optical axis 02 in a state where the portion 54 is opened, the observed portion can be illuminated in a circular shape. Further, by using the slit portion 54 in combination with the field stop portion 60 in a state where the interval between the

slit blades

54a and 54b is narrowed, the observed portion can be illuminated in an oval shape.

Accordingly, by rotating the turret 61, an opening 62 having an arbitrary size is selectively disposed on the illumination optical axis 02, thereby limiting the illumination range on the surface to be observed, and the slit blade 54a of the slit portion 54, By combining the width of 54b and the diameter of the opening 62 of the field stop 60, it is possible to irradiate the observation surface with the limited width and length.

Further, as shown in FIG. 4, the curved teardrop-shaped opening 64 is arranged on the illumination optical axis 02 in a state where the interval between the slit portions 54 is narrowed, and the turret 61 is arranged with a large-diameter arc end 64a and a small-diameter arc. By rotating between the end portion 64b, the length L of the slit interval formed by the slit portion 54 is limited, and the slit length can be continuously reduced.

In this embodiment, the turret 61 is configured to be driven to rotate by manual operation. The turret 61 is provided with a click part (not shown) having an appropriate configuration at a position where the center of each circular opening 63 coincides with the illumination optical axis 02, and the examiner operates the operation part to The desired circular opening 63 can be arranged and fixed on the illumination optical axis 02 by rotating the turret 61 so as to match the click portion.

In the curved teardrop-shaped opening 64, a click portion (not shown) is provided at a position where the centers of the large-diameter arc end 64a and the small-diameter arc end 64b coincide with the illumination optical axis 02, The click portion is not provided between the large-diameter arc end portion 64a and the small-diameter arc end portion 64b, and the turret 61 rotates at an arbitrary position between the large-diameter arc end portion 64a and the small-diameter arc end portion 64b. Can be stopped. Accordingly, the slit can be continuously reduced in length by stopping at an arbitrary position between the large-diameter arc end 64a and the small-diameter arc end 64b.

Further, the turret 61 may be configured to rotate electrically. In this case, a stepping motor as an actuator for driving the turret 61 and an appropriate driving force transmission mechanism are provided. The control unit 101 is configured to detect the rotation angle of the turret 61 by light detection means, for example, a photointerpreter, by measuring the number of steps of the stepping motor.

<Opening area detector>
The slit lamp microscope 1 according to the present embodiment has an opening area detection unit 59 provided with detection means for detecting the arrangement interval of the

slit blades

54a and 54b of the slit unit 54 and the rotation angle of the turret 61 of the field stop unit 60. ing. The control unit 101 determines the maximum luminous intensity value luminous intensity of the light source 51 based on the slit width detected by the opening area detection unit 59 and the opening area formed by the opening 62 of the turret 61.

The opening area detector 59 detects the width of the slit blade 54 a and the slit blade 54 b of the slit portion 54 and the opening diameter of the opening 62 of the field stop 60.
As for the width of the slit portion 54, the amount of rotation of a slit opening / closing knob (not shown) as a slit operation portion formed so as to be capable of rotating operation is detected by an encoder, and detection information is transmitted to the control portion 101.

In this case, the opening area detector 59 may be configured to detect the slit width value by detecting the amount of movement of the pair of

slit blades

54a and 54b by an appropriate detecting means. For example, the amount of movement of the

slit blades

54a and 54b can be measured by detecting the rotational speed of the drive shaft of an actuator that drives the

slit blades

54a and 54b.

Regarding the field stop 60, as described above, the rotation angle of the turret 61 having the plurality of openings 62 is determined by the light detection means in the case of manual operation and by the appropriate detection means in the case of electric operation. Are detected by measuring the number of steps, and each

opening

63a, 63b, 63c, 63d, 64 corresponding to the rotation angle is specified to obtain the opening diameter.
As a result, the aperture area detector 59 can obtain a composite aperture area from the combination of the slit width of the slit 54 and the aperture diameter of the aperture 62 of the field stop 60 obtained from the rotation angle of the turret 61. .

Further, the opening area detection unit 59 may be configured to detect the opening area based on the opening image of the anterior ocular segment image acquired by the imaging device 43 arranged in the observation system 6. In this case, it is necessary to detect and feed back the magnification of the zooming system.

The illumination diaphragm 56 is configured to be able to change the size of the translucent portion. The illumination stop 56 is particularly effective in fundus observation. For example, the illumination stop 56 has applications such as reducing the reflection of illumination light by the cornea Ec or the crystalline lens and adjusting the brightness of the illumination light.

[Background lighting system]
The background illumination light 20 irradiates the eye E with background illumination light. The background illumination light is applied to a region around the irradiation region of the illumination light applied to the eye E by the illumination system 8. Note that the background illumination light irradiation region only needs to include at least the surrounding region. For example, the irradiation area of the background illumination light may overlap with at least a part of the irradiation area by the illumination system 8.

The background illumination system 20 includes a light source (background light source). The background light source includes at least a visible light source that outputs visible light. This visible light is used, for example, for visual observation and photographing. The background light source may include an infrared light source that outputs infrared light. This infrared light is used, for example, for observation and photographing of the meibomian glands.

When the background illumination system 20 includes both a visible light source and a background light source, these light sources are used alternatively, for example. The background illumination system 20 may include one or more lenses that focus the light output from the background light source. Reference symbol O3 indicates the optical axis of the background illumination system 20 (background illumination optical axis).

The light output from the background light source is reflected by the mirror 12 (after being collected by the lens) and applied to the eye E. The irradiation area of the background illumination light includes an area around the irradiation area of the eye E to be examined by the illumination system 8.

[Control system configuration]
A control system of the slit lamp microscope 1 will be described with reference to FIG.
The control system of the slit lamp microscope 1 is configured around the control unit 101. Note that at least a part of the configuration of the control system may be included in the computer 100.

(Control part)
The control unit 101 controls each unit of the slit lamp microscope 1.
The control unit 101 controls the observation system 6, the illumination system 8, and the background illumination system 20. Control of the observation system 6 includes control of the variable power optical system 32, control of the diaphragm 33, control of charge accumulation time, sensitivity, frame rate, etc. of the image sensor 43. Control of the illumination system 8 includes control of the light source 51, the light source luminous intensity detection unit 58, the slit unit 54 constituting the light beam control unit 70, the field stop unit 60 and the aperture area detection unit 59, and the illumination stop 56. Control of the background illumination system 20 includes control of a background light source.

The control unit 101 includes a microprocessor, a RAM, a ROM, a hard disk drive, and the like. A control program is stored in advance in a storage device such as a ROM or a hard disk drive. The operation of the control unit 101 is realized by the cooperation of this control program and hardware. The control unit 101 is disposed in the apparatus main body (for example, in the base 4) of the slit lamp microscope 1 or the computer 100.

[Display section]
The display unit 102 displays various information under the control of the control unit 101. The display unit 102 includes a display device such as a flat panel display such as an LCD. The display unit 102 may be provided in the apparatus main body of the slit lamp microscope 1 or may be provided in the computer 100.

[Operation section]
The operation unit 103 includes an operation device and an input device. The operation unit 103 includes buttons and switches (for example, the operation handle 5 and the illumination intensity operation unit 18) provided on the slit lamp microscope 1 and operation devices (such as a mouse and a keyboard) provided on the computer 100. The operation unit 103 may include an arbitrary operation device or input device such as a trackball, an operation panel, a switch, a button, or a dial.

In FIG. 5, the display unit 102 and the operation unit 103 are shown separately, but at least a part of them can be configured integrally. As a specific example, a touch screen can be used.

[Light source intensity detector]
Since the luminous intensity of the light source 51 is substantially correlated with the applied power, it is possible to control the luminous intensity of the light source 51 by limiting the applied power, but as shown in FIG. 2, in the slit lamp microscope 1 according to the present embodiment. Is provided with a light source light intensity detector 58 for measuring and detecting the light intensity of the light source 51.
The light source luminous intensity detection unit 58 is configured to directly monitor the luminous intensity of the light source 51. When the light quantity is directly monitored in this way, the light quantity varies or the light quantity decreases due to deterioration of the light source. Even if it exists, the slit image of appropriate illumination intensity can be projected.

In this case, the light source luminous intensity detection unit 58 may be configured by a photodetector, arranged near the light source 51, and configured to receive the scattered light component of the light source 51. One end may be arranged, the scattered light of the light source may be taken in from the end face of the optical fiber, and a photodetector may be arranged near the other end. Further, a mirror that reflects a part of the light beam may be disposed in the optical path 02, and the reflected light may be received by the photodetector.

[Light intensity control of light source by opening area of opening]
The meaning and significance of “maximum luminous intensity value control of light source based on slit width and field stop diameter” in the present invention will be described below.

Illumination light from the light source 51 is collected by a condenser lens 53 and passes through an opening 71 combined with a slit 54 and a field stop 60 to form a light source image near the mirror 12 from the imaging lens 55. To do.
The light source image is formed near the fundus Er of the eye E via the mirror 12. The image of the opening 71 is formed on the observation site via the mirror 12 by the imaging lens 55. When the cornea Ec is observed, alignment is performed so that the cornea Ec matches the observation position.

When the light intensity of the light source 51 is constant, the illuminance of the aperture image formed on the cornea Ec does not change even when the aperture area of the aperture 71 is changed. However, the illuminance of the light source image on the fundus Er decreases as the aperture area decreases, and increases as the aperture area increases.

The opening area of the opening 71 is a combination of the width of the slit portion 54 and the diameter of the field stop 60, and is arbitrarily set by the examiner depending on the observation site and the observation method. In order to observe the observation site better and in detail, the light intensity of the light source 51 is increased (brightened), and the illuminance of the aperture image on the test portion is increased for observation.
At this time, most of the irradiated light beam passes through the cornea Ec to reach the fundus Er and illuminates the fundus Er. Therefore, conventionally, the safe value of fundus illuminance is not exceeded under any illumination conditions. Some have been configured to limit the amount of light volume or to alert a warning.

However, even if the luminous intensity of the light source 51 is constant, changing the opening area of the opening 71 changes the fundus illuminance. Therefore, even when the fundus illuminance reaches the upper limit of the safe value at a certain opening area, If the opening area is narrowed, the fundus illuminance can have a margin with respect to the safe value. In this case, if it is desired to observe the cornea Ec brighter, the luminous intensity of the light source 51 can be increased to increase the illuminance of the aperture image on the cornea Ec. On the contrary, when the opening area is enlarged, the fundus illuminance exceeds the safe value, so the luminous intensity of the light source 51 must be lowered.

Conventionally, the light intensity of the light source 51 is set so that the illuminance of the fundus oculi Er is suppressed to a safe value or less with the opening fully opened, so that there is a margin with respect to the fundus safe value with the slit portion 54 narrowed. Even under certain conditions, bright observation was not possible.
Therefore, in the present invention, the width of the slit portion 54 and the diameter of the field stop 60 are detected, and the maximum luminous intensity of the light source 51 is made variable in accordance with the detected and combined aperture area.

In the slit lamp microscope 1 according to the present embodiment, when the slit width and the field stop diameter are set by the examiner, the control unit detects the slit of the slit unit 54 detected by the aperture area detection unit 59. Based on the width and the field stop diameter selected in the field stop 60, the aperture area of the opening 71 obtained in combination is obtained, the maximum light intensity value of the light source 51 is set, and the light intensity value of the light source 51 is the maximum light intensity value. It is configured not to be set beyond this.

As shown in FIG. 5, the control unit 101 includes a storage unit 101 a, and the storage unit 101 a generates observation light corresponding to the opening area based on the slit width value and the field stop diameter set by the examiner. Even when the eye fundus Er is irradiated, data including a maximum light intensity value of an appropriate light source that does not exceed the safe illuminance with respect to the eye fundus to be examined is stored in advance.
The control unit 101 determines the maximum luminous intensity value of the light source 51 with reference to the data in the storage unit 101a based on the aperture area including the slit width and the selected field stop diameter detected by the aperture area detection unit 59.

Accordingly, in the examination, the examiner performs observation by appropriately operating the opening / closing of the slit portion 54 and the opening diameter of the field stop portion 60 as necessary, but the width of the slit portion 54 set by the examiner and the field stop portion are set. The maximum light intensity value of the light source 51 corresponding to the opening area value is determined by the control unit 101 according to the opening area having the opening diameter of 60, and the examiner appropriately adjusts the light intensity of the light source 51 if it is equal to or less than the maximum light intensity value. Necessary observation and inspection can be performed by changing the operation, and the luminous intensity of the light source 51 cannot be increased beyond the maximum luminous intensity value corresponding to the determined opening area value.

When the examiner tries to set the luminous intensity of the light source 51 to be greater than or equal to the maximum luminous intensity value, a warning that “the maximum luminous intensity value has been reached” is displayed on the display unit 102 or the auditor is warned by voice. May be.

[Description of operation]
A procedure for performing light intensity control of the light source 51 based on the aperture area when performing eye examination using the slit lamp microscope 1 according to the present embodiment will be described with reference to the flowchart of FIG.

When using the slit lamp microscope 1, the operator sets or changes the width of the slit portion 54 and the field stop diameter of the field stop portion 60 in accordance with the specific circumstances of the optometry (S1).

Next, the aperture area detector 59 detects the set or changed slit width and field stop diameter, and sends a detection signal to the controller 101 (S2).

Next, the control unit 101 obtains an opening area obtained by combining the slit width and the field stop diameter, and the set opening area stored in the storage unit 101a and the observation light corresponding to the opening area are obtained from the eye to be examined. The maximum luminous intensity value of the light source 51 corresponding to the obtained aperture area is acquired from the data table including the appropriate maximum luminous intensity value of the light source that does not exceed the safe value of the fundus illuminance even when the fundus is irradiated. (S3).

Next, the control unit 101 detects the actual light intensity of the light source 51 set or changed by the light source light intensity detection part 58, and acquires the light intensity (S4). Then, the control unit 101 determines whether or not the light intensity of the light source 51 detected and acquired in S4 is equal to or less than the maximum light intensity value acquired from the storage unit 101a in S3 (S5).

When the control unit 101 determines that the light intensity of the light source 51 is equal to or less than the maximum light intensity value acquired from the storage unit 101a in S3, the control unit 101 allows and determines the light intensity set or changed by the examiner and ends the control. (S6).

On the other hand, if the control unit 101 determines that the luminous intensity of the light source 51 is not less than or equal to the maximum luminous intensity value acquired from the storage unit 101a in S3, the luminous intensity of the light source 51 is set to the set or changed aperture area. The maximum light intensity value of the corresponding light source is set and the control ends.

In the present embodiment, the case where the background illumination system 20 is provided has been described as an example, but the present invention is not limited to the above embodiment, and the background illumination system 20 may not be provided.

Since the present invention relates to the slit lamp microscope, it has wide industrial applicability.

01 Observation Optical Axis 02 Illumination Optical Axis 03 Background Illumination Optical Axis 1 Slit Lamp Microscope 2 Table 3 Movement Mechanism 4 Base 5 Operation Handle 6 Observation System 8 Illumination System 9 Lens Body 9a Eyepiece 10 Jaw Base 10a Jaw Base Part 10b Forehead rest 11 Observation magnification operation knob 12 Reflection mirror
DESCRIPTION OF SYMBOLS 15 Support part 16 Support arm 17 Support arm 18 Illumination intensity operation part 20 Background illumination system 31 Objective lens 32 Variable magnification optical system 33 Diaphragm 34 Beam splitter 35 Relay lens 36 Prism 36a Optical element 36b Optical element 37 Eyepiece 41 Relay lens 42 Mirror 43 Image sensor 51 Light source 52 Relay lens 53 Condenser lens 54 Slit part (light flux control part)

54a Slit blade

54b Slit blade 55 Condenser lens 56 Illumination stop 58 Light source luminous intensity detection unit 59 Opening area detection unit (light flux control unit)
60 Field stop (beam controller)
61 turret 62 opening 63a circular opening 63b circular opening 63c circular opening 63d circular opening 64 curved teardrop-shaped opening 65 illumination light beam 70 light beam control unit 71 opening unit 100 computer 101 control unit 101a storage unit
102 Display unit 103 Operation unit E Eye Ec Cornea Ep Iris Er Fundus P Light imaging position L Length of slit interval

Claims

In a slit lamp microscope, a slit lamp characterized by having a detecting means for detecting a condition of an illumination system, and controlling a luminous intensity of an illumination light source based on a detection result of the detecting means.
The slit lamp microscope according to claim 1, wherein the illumination system condition is a light amount of a light source.
An illumination system that has a light source that outputs illumination light, and that irradiates the subject's eye with observation light whose area is limited by passing through a light beam control unit capable of changing the area of the opening; and the observation light A slit lamp microscope comprising an observation system for observing return light from the subject eye, and a control unit for controlling at least the operation of the illumination system,
A slit lamp microscope comprising: an opening area detection unit that detects an area of the opening, wherein the control unit controls the light intensity of the light source based on the opening area detected by the opening area detection unit.
The said light beam control part has a slit part, and the said slit part has a pair of slit blade with which arrangement | positioning space | interval is variable at least, It is formed so that the space | interval of the said slit blade can be detected. A slit lamp microscope described in 1.
The luminous flux control unit has a field stop, and by selectively arranging a plurality of apertures with different diameters on the optical axis, the diameter of the luminous flux passing through the aperture can be made variable so that the arranged aperture can be detected. The slit lamp microscope according to claim 3, wherein the slit lamp microscope is formed.
The light beam control unit includes a slit part and a field stop part provided on the side opposite to the light source of the slit part, and the field stop part is disposed so as to be rotatable in a direction orthogonal to the light beam. The opening is composed of a plurality of circular openings arranged concentrically in the turret body and a single curved teardrop-shaped opening, and the curved teardrop-shaped opening has a large diameter. An arc end, a small-diameter arc end concentrically arranged on the large-diameter arc end, and a width dimension gradually decreases from the large-diameter arc end to the small-diameter arc end. The slit lamp according to claim 3, wherein the curved teardrop-shaped opening can continuously change and control the width of the light beam that has passed through the slit. microscope.
When the examiner sets the arrangement interval of the pair of slit blades of the slit portion and the opening diameter of the field stop portion, the control unit detects the pair of slit blades detected by the opening area detector. The maximum light intensity value of the light source is determined based on the arrangement interval and the aperture diameter of the field stop, and the light intensity value of the light source is set to be equal to or less than the maximum light intensity value. Item 7. The slit lamp microscope according to any one of Items 3 to 6.
The control unit includes a storage unit, and the storage unit includes an opening area composed of a set arrangement interval width of the pair of slit blades and an opening diameter of the field stop unit, an arrangement interval of the pair of slit blades, and a field stop. Storing the data including the maximum luminous intensity value of an appropriate light source that does not exceed the fundus illuminance safety value even when the observation light corresponding to the opening diameter of the unit is irradiated on the fundus of the eye to be examined. The unit refers to the data of the storage unit, and determines the maximum luminous intensity value of the light source based on the slit width of the slit unit detected by the aperture area detection unit and the aperture diameter of the field stop unit. The slit lamp microscope according to any one of claims 3 to 7.
The slit lamp microscope according to any one of claims 3 to 8, wherein the opening area detection unit acquires the slit width value by detecting an operation amount of the slit operation unit.
The slit lamp microscope according to any one of claims 3 to 8, wherein the opening area detector detects a slit width value by detecting a movement amount of the pair of slit blades.
The opening area detection unit detects an opening area based on an opening image of an anterior ocular segment image acquired by an imaging device arranged in an observation system. Slit lamp microscope.
The said opening area detection part detects the opening diameter formed of the opening part of the said turret by measuring the step of the stepping motor which drives the said turret, The any one of Claims 3 thru | or 8 characterized by the above-mentioned. A slit lamp microscope described in 1.
The slit lamp microscope according to any one of claims 3 to 8, wherein the opening area detection means detects an opening diameter by detecting a rotation angle of the turret by a light detection unit.