JP3441156B2 - Ophthalmic equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmic apparatus, and more particularly to an alignment adjusting mechanism for aligning a measuring system of the ophthalmic apparatus with a predetermined positional relationship with an eye to be examined.

[0002]

2. Description of the Related Art Ophthalmologic devices such as a non-contact tonometer and an objective ocular refracting power measuring device perform alignment adjustment of the eye to be inspected and the measuring system of the device in a predetermined positional relationship during measurement, that is, vertical and horizontal movements. It is necessary to adjust the position and the working distance.

Conventionally, as an alignment adjustment of an ophthalmologic apparatus, an alignment index is projected onto an eye to be inspected, and a reflection image of the apex of the cornea of the eye to be inspected is received by an observation system together with an anterior eye image of the eye to be inspected, and the joystick is observed on a television monitor or the like. There is known an alignment adjusting mechanism which drives a sliding mechanism by means such as the above so that an optical system such as a measuring system has a predetermined positional relationship with an eye to be inspected.

[0004]

However, the alignment adjustment as described above requires the measurer to operate the joystick or the like while looking at the television monitor or the like. Therefore, for example, the alignment required for a non-contact tonometer is required. In a device with high accuracy, a measurer unaccustomed to the alignment operation takes time to adjust the alignment, and the accuracy is low.

Therefore, in order to handle an apparatus that requires high-precision alignment, the operator needs to be skilled in operation, and sufficient training is required to perform a complete operation.

The present invention has been devised in view of the above drawbacks, and an object of the present invention is to easily and accurately perform alignment between an eye to be inspected and an apparatus measuring system, etc., regardless of the proficiency of the measurer. To provide an ophthalmologic apparatus.

[0007]

The present invention is characterized by having the following constitution in order to solve the above problems.

(1) An observation optical system for observing the anterior segment of the eye to be inspected on a monitor is provided, and the eye to be inspected is moved to a predetermined X position with respect to the measurement system.
In an ophthalmologic apparatus that requires alignment in the YZ direction, a first index projection optical system that projects a first index for alignment from the optical axis direction of the observation optical system toward the cornea of the eye to be examined, and corneal reflection A first index detection optical system that detects a one-dimensional or two-dimensional position of a first index image, which is an image , from a direction of an optical axis of the observation optical system by a position detection element; and an optical axis of the first index projection optical system. A second index projection optical system having optical axes that intersect and projecting a second index for alignment toward the cornea of the eye; and a second index projection optical system with respect to the optical axis of the first index projection optical system. having an optical axis and symmetrical optical axis, the corneal anti
The second index detection optical system that detects the one-dimensional or two-dimensional position of the second index image that is a projection image , and the measurement based on the detection results of the first index detection optical system and the second index detection optical system. Drive control means for three-dimensionally aligning the system and control of the drive control means are stopped, and alignment information is displayed on the monitor based on the detection results of the first index detection optical system and the second index detection optical system. And a mode switching means for switching between the automatic alignment mode for performing alignment by the drive control means and the manual alignment mode, and having a manual alignment mode in which the examiner manually performs alignment based on the alignment information. And

(2) An ophthalmologist that has an observation optical system for observing the anterior segment of the eye to be inspected with a monitor, and it is necessary to position either the left or right eye to be inspected in a predetermined XYZ direction position with respect to the measurement system. In the apparatus, a first index projection optical system that projects a first index for alignment from the optical axis direction of the observation optical system toward the cornea of the eye to be examined , and a first index that is a corneal reflection image
It has a first index detecting optical system for detecting a one-dimensional or two-dimensional position of an image from the optical axis direction of the observation optical system by a position detecting element, and an optical axis intersecting the optical axis of the first index projecting optical system. A second index projection optical system for projecting a second index for alignment toward the cornea of the eye to be examined, and a light symmetrical with the optical axis of the second index projection optical system with respect to the optical axis of the first index projection optical system. having an axis, a second index detecting optical system for detecting a one-dimensional or two-dimensional position of the second index image is a corneal reflection image, the first index detecting optical system and the second index detection optical system of the detection result Based on the drive control means for three-dimensionally aligning the measurement system and the detection results of the first index detection optical system and the second index detection optical system, the examiner manually performs rough alignment. Display the necessary alignment information on the monitor, Display control means for displaying on the monitor the completion of rough alignment capable of three-dimensional alignment by the drive control means.

[0010]

[0011]

[0012]

[0013]

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a non-contact tonometer will be described below with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an alignment optical system and a control system of the apparatus of the embodiment. The non-contact tonometer is a device for injecting compressed air to the cornea of the eye to deform the cornea into a predetermined state and measuring the intraocular pressure of the eye to be inspected directly or indirectly based on the air pressure detected at that time. However, the description of the measuring mechanism itself is omitted because it is not relevant to the present invention.

[Alignment Optical System] The alignment optical system is divided into an observation optical system, a reticle projection optical system, a front index projection optical system, a front index detection optical system, a distance target projection optical system, and a distance target detection optical system. explain.

(Observation optical system) 1 is an observation optical system, and L indicates its optical axis. A nozzle 2 that blows out a gas for corneal deformation is arranged on the optical path of the observation optical system, and its axis coincides with the optical axis L. A half mirror-3, an objective lens 4, a filter 5, a half mirror-6, and a TV camera 7 are arranged on the optical axis L. The filter 5 has a characteristic of transmitting the wavelength of the light flux of the front index projection optical system, which will be described later, and not transmitting the wavelength of the light flux of the distance index projection optical system, and is unnecessary for the TV camera 7 and the detection elements of the front index detection optical system. Prevents noise light from reaching.

Reference numeral 8 is an illumination light source for observing an eye to be inspected, which emits near infrared light, and 9 is a TV monitor for displaying an image captured by the TV camera 7. The anterior ocular segment image of the eye E to be inspected illuminated by turning on the illumination light source 8 is formed on the image pickup surface of the TV camera 7 by the objective lens 4 through the half mirror-3, the filter 5, and the half mirror-6. Then, it is displayed on the TV monitor 9.

(Reticle projection optical system) 10 represents a reticle projection optical system. The reticle projection optical system 10 includes a light source 11 and
It is composed of a reticle plate 12 and a projection lens 13. The reticle of the reticle plate 12 illuminated by the light source 11 is a
The image is formed on the image pickup element of the TV camera 7 by the projection lens 13 via the Fumilla 6 and is displayed on the TV monitor 9 so as to overlap with the anterior segment image.

(Front index projection optical system) 20 is a front index projection optical system, and the front index projection optical system 20 is an illumination light source 8
It is composed of a light source 21 such as a near-infrared LED which emits light of a wavelength close to and a projection lens 22. The light source 21 includes an illumination light source 8
The output is modulated at a predetermined frequency in order to prevent the light flux of the above from becoming noise to the front index detection optical system described later.

The light from the light source 21 is converted into a parallel light flux by the projection lens 22, and then reflected by the half mirror 3 to have an optical axis L.
The light passes through the inside of the nozzle 2 and the like and is irradiated onto the cornea Ec. This light flux is specularly reflected by the cornea Ec and forms a visual target i1 which is a virtual image of the light source 21 on the eye E to be inspected. The luminous flux of the optotype i1 forms an image of the optotype i1 on the image pickup element of the TV camera 7 by the observation optical system.

(Front index detection optical system) 30 is a front index detection optical system, and the front index detection optical system 30 is the field stop 3.
It is composed of a one- and two-dimensional position detecting element 32, an objective lens 4, a filter 5, and a half mirror 6 which are shared with the observation optical system. The diameter of the field stop 31 is set so that unnecessary light does not enter the detection element 32, and the light flux of the optotype i1 located at a substantially proper position with respect to the reticle image on the TV camera 7 enters the detection element 32. Has been done. Various sensors such as CCD and PSD can be used as the two-dimensional position detecting element 32. Further, instead of the two-dimensional position detecting element, a four-divided division type photo detecting element may be used.

The front index light beam specularly reflected by the cornea Ec is guided to the front index detection optical system 30 by the half mirror 6, passes through the field stop 31, and is received by the detection element 32. The detection element 32 detects the vertical and horizontal positions of the eye to be inspected with respect to the measurement axis (observation optical axis L) based on the two-dimensional position of the luminous flux of the index i1 incident on the element surface.

(Distance index projection optical system) 40 is a distance index projection optical system, and M is its optical axis. Optical axis M is optical axis L
The optical axes are inclined with respect to each other, and the two optical axes intersect at a position away from the nozzle 2 by a predetermined working distance. The crossing angle of the optical axis M with respect to the optical axis L is preferably 20 degrees to 40 degrees. On the optical axis M, a light source 41 such as an LED having a wavelength different from that of the light source 21 and a projection lens 42 are arranged.

The light emitted from the light source 41 is made into a parallel light flux by the projection lens 42 and is irradiated on the cornea Ec along the optical axis M. The light beam specularly reflected by the cornea Ec forms an index i2 which is a virtual image of the light source 41.

(Distance index detection optical system) 50 is a distance index detection optical system, and N is its optical axis. Optical axis N and optical axis M
Has an axis symmetrical to the optical axis L, and the optical axis N intersects the optical axis M on the optical axis L. A light receiving lens 51, a filter 52, and a one-dimensional detection element 53 are provided on the optical axis N. The filter 52 transmits the light of the wavelength of the light source 41 of the distance index projection optical system 40, and the illumination light source 8 and the front index projection optical system 20.
Has a characteristic of being non-transmissive to the light of the wavelength of the light source 21 and prevents the light of the index i1 and the light of the illumination light source 8 from entering the one-dimensional detection element 53 and becoming noise.

The cornea reflected light flux of the light source 41 forming the index i2 is passed through the filter 52 by the light receiving lens 51 to
It is incident on the dimension detecting element 53. When the eye to be inspected moves in the axial direction of the optical axis L (forward and backward direction), the image of the index i2 by the light receiving lens 51 also moves in the detection direction of the one-dimensional detection element 53. The position of the eye to be inspected in the front-back direction is detected from the deviation of the index image on the one-dimensional detection element 53.

A cylindrical lens having a generatrix direction in the detection direction may be arranged in front of the one-dimensional detection element 53.

[Control System] The signals output from the two-dimensional detection element 32 and the one-dimensional detection element 53 are subjected to predetermined processing by the detection processing circuits 60 and 61, respectively, and input to the control circuit 62. 63 is an X-direction drive system that moves the measurement system and the alignment system in the vertical direction (X direction) with respect to the observation optical axis L, and 64 is a Y-direction drive system that moves the measurement system and the alignment system in the horizontal direction (Y direction) with respect to the observation optical axis L, Reference numeral 65 denotes a Z-direction drive system that moves along the optical axis L direction (Z direction). Each of these drive systems is composed of a motor and a motor drive circuit.

The operation of the apparatus having the above configuration will be described. The anterior ocular segment image of the subject's eye E illuminated by the illumination light source 8 is received by the TV camera 7 via the observation optical system together with the reticle image by the reticle optical system and is received by the TV monitor 9.
Projected on. While observing the anterior segment image and the reticle image on the TV monitor 9, the examiner operates a joystick (not shown) to bring the iris or pupil of the anterior segment image and the reticle image into a substantially predetermined positional relationship and focus. The adjustment allows the device to be roughly aligned with the eye to be examined.

In this state, the luminous fluxes of the indexes i1 and i2 are incident on the two-dimensional detection element 32 and the one-dimensional detection element 53 of each detection optical system.

When the index image is incident on the detection element 53, the detection element 53 outputs a signal corresponding to the position of the index image on the surface of the one-dimensional detection element. This signal is input to the control circuit 62 via the signal detection circuit 61. Similarly, the two-dimensional detection element 32 outputs a signal corresponding to the position of the index image on the detection surface and is input to the control circuit 62.

When coarse alignment is performed and the two-dimensional detection element 32 and the one-dimensional detection element 53 detect the index image,
The control circuit 62 displays a message or the like indicating that the rough alignment has been completed on the television monitor 9 to notify the examiner.
When only one of the index images is detected, if the examiner is individually informed of that fact, the examiner can perform the operation more easily.

The control circuit 62 notifies the examiner of a message or the like indicating that the rough alignment has been completed, and then, after a certain period of time, based on the positional information of the two-dimensional detection element 32, the X-direction drive system 6
The 3 and Y direction drive systems 64 are respectively activated to operate the Z direction drive system 65 based on the positional information of the one-dimensional detection element 53. When the control circuit 62 determines that the device has moved due to the operation of each drive system and the index image has reached the position within the predetermined allowable range, the operation of each drive system is stopped and the alignment is completed. When the alignment is completed, a signal for automatically operating the measurement system is issued to perform the measurement.

In the above example, when the rough alignment is completed, the precise alignment and the measuring operation are automatically started. However, after the examiner is notified of a message or the like, the examiner shows the figure. Not press the measurement start switch,
The precise alignment and the measurement operation may be performed in conjunction with each other.

In the above embodiment, the two-dimensional position detecting element is arranged in the front index detecting optical system, and the distance index detecting optical system has one unit.
Although the dimension detecting element is arranged, this arrangement may be reversed. In this case, the two-dimensional position detecting element of the distance index detecting optical system detects the distance and either the vertical direction or the horizontal direction, and the one-dimensional detecting element of the front index detecting optical system detects the remaining one of the vertical direction and the horizontal direction. Is set to detect. Also, both index detection optical systems may be two-dimensional position detection elements, and all directions are one- dimensional position detection elements.
It may be an element .

In the present embodiment, the alignment system is composed of two systems, a front index projection / detection optical system along the optical axis of the observation optical system and an oblique distance index projection / detection optical system. Without being limited to this, index light beams are projected from two directions inclined to the optical axis of the observation optical system, and the position is detected by photodetectors arranged at the same angle with respect to the optical axis of the observation optical system, The position information may be obtained by decomposing each element in the front-rear, left-right, and up-down directions.

Further, in the conventional non-contact tonometer, the alignment is manually performed, and the adjustment of the up / down / left / right and the working distance is performed based on the display of the arrow or the like on the monitor or the like. A means for switching to the alignment by means is provided, and when the manual mode is selected, a marker for indicating the alignment direction (and amount) based on the signal from the detection element is provided.
May be displayed on a monitor or the like. By doing so, it becomes possible to measure even those that are difficult to be automatically aligned. As described above, the present embodiment can be variously modified, and these modifications are also included in the present invention within the scope of the same technical idea.

[0038]

As described above, according to the present invention,
Easy and accurate alignment regardless of the operator's skill level
Can be made.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an alignment optical system and a control system of an apparatus according to an embodiment.

[Explanation of symbols]

1 Observation optical system 20 Front index projection optical system 30 Front index detection optical system 40 Distance index projection optical system 50 Distance index detection optical system 62 control circuit 63 X-direction drive system 64 Y direction drive system 65 Z direction drive system L observation optical axis

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-154107 (JP, A) JP-A-5-293084 (JP, A) JP-A-6-7302 (JP, A) JP-A-1- 300928 (JP, A) JP 5-245112 (JP, A) JP 1-164351 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) A61B 3/00-3 / 16

Claims (2)

(57) [Claims] 1. An observation optical system for observing the anterior ocular segment of an eye to be inspected on a monitor, the eye to be inspected in predetermined XYZ directions with respect to a measurement system.
In the ophthalmologic apparatus that requires alignment with the position of, the first index projection optical system that projects the first index for alignment from the optical axis direction of the observation optical system toward the cornea of the eye, and the corneal reflection image A first index detection optical system that detects a one-dimensional or two-dimensional position of a certain first index image from the optical axis direction of the observation optical system by a position detection element intersects the optical axis of the first index projection optical system. A second index projection optical system having an optical axis and projecting a second index for alignment toward the cornea of the eye to be examined; and an optical axis of the second index projection optical system with respect to the optical axis of the first index projection optical system. It has an optical axis symmetrical with
A second index detecting optical system for detecting the one-dimensional or two-dimensional position of a certain second index image , the first index detecting optical system and the second index detecting optical system.
Based on the detection result of the index detection optical system, drive control means for three-dimensionally aligning the measurement system and control of the drive control means are stopped, and the first index detection optical system and the second index detection optical system. Based on the detection result of, the alignment information is displayed on the monitor, and the examiner has a manual alignment mode in which the operator manually performs alignment based on the alignment information, and an automatic alignment mode and a manual alignment mode in which the drive control means performs alignment. An ophthalmologic apparatus, comprising: a mode switching unit for switching between. 2. An ophthalmologic apparatus which has an observation optical system for observing the anterior segment of the eye to be inspected with a monitor and which is required to position either the left or right eye to be inspected in a predetermined XYZ direction position with respect to the measurement system. In the first, the first index for alignment is projected from the optical axis direction of the observation optical system toward the cornea of the eye to be examined.
A target projecting optical system, a first index detecting optical system for detecting the position detecting device in the optical axis direction of a one-dimensional or two-dimensional position of the first index image is a corneal reflection image the observation optical system, the first A second index projection optical system having an optical axis intersecting the optical axis of the index projection optical system and projecting a second index for alignment toward the cornea of the eye to be examined, and an optical axis of the first index projection optical system. Has an optical axis that is symmetrical with the optical axis of the second index projection optical system,
A second index detecting optical system for detecting a one-dimensional or two-dimensional position of the second index image is a corneal reflection image, based on the first index detecting optical system and the second index detection optical system of the detection result, the Alignment information necessary for the operator to perform rough alignment manually based on the drive control means for three-dimensionally aligning the measurement system and the detection results of the first index detection optical system and the second index detection optical system. Is displayed on the monitor, and display control means for displaying on the monitor that the rough alignment capable of three-dimensional alignment by the drive control means is completed, and an ophthalmologic apparatus.