JP4125091B2 - Ophthalmic imaging equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ophthalmologic photographing apparatus used in an ophthalmic clinic or a mass examination.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a fundus camera that photographs a desired part of a subject's eye by providing a light source for guiding the subject's eye to a desired photographing part and fixing the light source to the subject's eye is disclosed in, for example, Japanese Patent Laid-Open No. 8-252224. Known in publications and the like.
[0003]
FIG. 6 shows the structure of a conventional fundus camera. On the optical path behind the objective lens 1 facing the eye E, a perforated mirror 2 having an opening in the center, a focus lens 3, a photographing lens 4, A rotatable mirror 5 is arranged. Above the mirror 5 is a fixation optical system, where a relay lens 6, a liquid crystal shutter 7 in which a large number of liquid crystal elements for fixing the eye to be examined are arranged, and a light source 8 are arranged.
[0004]
A field lens 9, a field stop 10, an imaging lens 11, and an imaging unit 12 are disposed behind the mirror 5. A lens 13, a ring diaphragm 14, and a light source 15 are disposed on the optical path in the incident direction of the perforated mirror 2. The control means 16 is connected to the image pickup means 12, the television monitor 17, the photographing switch 18, and the fixation target moving switch 19, respectively.
[0005]
The examiner turns on the liquid crystal element at the desired position of the liquid crystal shutter 7 and presents it to the subject in order to photograph the desired part of the eye to be examined. The position information of the liquid crystal shutter 7 is converted into an electric signal, a character C is generated at a position based on the information, and is synthesized on the observation screen as shown in FIG.
[0006]
When the desired part is changed, for example, when the fixation target moving switch 19 including a cross key is operated to move the lighting position of the liquid crystal shutter 7, the character C on the observation screen also moves the liquid crystal shutter 7. Move on the screen in conjunction with.
[0007]
[Problems to be solved by the invention]
However, in the above-described conventional example, especially in the case of non-mydriatic photography without using a mydriatic agent, fixation fixation presents a bright spot in the dark and causes fixation, and at this time, in order to stabilize fixation Generally, the bright spot is made small. However, in order to move the luminescent spot and guide the eye to a desired position while maintaining the size for fixation fixation, the luminescent spot is small and difficult to see, and the subject loses sight of the bright spot. There is a problem that it is easy.
[0008]
An object of the present invention is to solve the above-described problems, change the size of the fixation target during movement of the fixation target, and return the fixation target to the original size again at a desired position. Is to provide.
[0009]
[Means for Solving the Problems]
To achieve the above object, an ophthalmologic photographing apparatus according to the present invention provides a fixation target presenting means for presenting a fixation target for inducing fixation of the eye to be examined, and a presentation for instructing a presentation position of the fixation target Position fixing means, wherein the fixation target presenting means changes the size of the fixation target to be presented while moving the fixation target to the instructed fixation target presentation position.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail based on the embodiment shown in FIGS.
In FIG. 1, on the optical path behind the objective lens 21 facing the eye E, a perforated mirror 22 having an opening at the center, a focus lens 23, a photographing lens 24, and a rotatable rotating mirror 25. A field lens 26, a field stop 27, an imaging lens 28, and an imaging means 29 are arranged. Above the mirror 25, an imaging lens 30, a liquid crystal shutter 31, and a light source 32 are arranged as a fixation optical system for the eye E.
[0011]
A lens 33, a ring stop 34, and an observation light source 35 are arranged on the optical path in the incident direction of the perforated mirror 22. The ring stop 34 is arranged substantially conjugate with the perforated mirror 22 with respect to the lens 33.
[0012]
The output of the imaging means 29 is connected to the control means 41, and a television monitor 42, a photographing switch 43, a fixation target moving switch 44, and a position detector 45 of the imaging lens 28 are connected to the control means 41. Also has a fixation lamp control function for the liquid crystal shutter 31.
[0013]
During observation, the light beam emitted from the observation light source 35 passes through the opening of the ring diaphragm 34 and the lens 33, is reflected to the left by the mirror of the perforated mirror 22, and passes through the objective lens 21 to the fundus Er of the eye E to be examined. Illuminate. The reflected light beam at the fundus Er passes through the pupil Ep, the objective lens 21, the aperture of the apertured mirror 22, the focus lens 23, the photographing lens 24, and the field lens 26, and once forms a fundus image near the field stop 27. Then, the image is formed again on the photographing means 29 through the imaging lens 28. The fundus image Pr formed on the photographing unit 29 is converted into a video signal and displayed on the television monitor 42 via the control unit 41.
[0014]
The photographer observes the fundus moving image displayed on the television monitor 42, adjusts the focus lens 23 to aim the fundus image Pr, and further fixes the fixation target in order to photograph the desired part of the eye E. The movement switch 44 is operated. The situation at this time is the same as the screen of the conventional television monitor 17 shown in FIG.
[0015]
The rotating mirror 25 is raised, and the image of the liquid crystal shutter 31 illuminated by the light source 32 is presented to the eye E by the objective lens 21 via the imaging lens 30 and the rotating mirror 25. The photographer guides the subject's eye E to a desired site with the liquid crystal shutter 31 and then presses the photographing switch 43 to cause the observation light source 35 to emit light and record the fundus image in the storage means inside the control means 41 as a still image. FIG. 2 shows the positional relationship between the opening 31a of the liquid crystal shutter 31 and the light shielding portion 31b at this time.
[0016]
FIGS. 3A to 3C show the state of the opening 31a and the light shielding part 31b when the fixation target is moved. 3A shows a fixation presentation position before movement, FIG. 3B shows the fixation presentation position after movement, and FIG. 3C shows the fixation presentation position after movement. When the fixation target moving switch 44 is operated to move the position of the fixation target from (a) to (c), the number of the openings 31a is increased in the middle of the movement (b). The target is enlarged, and after the movement, as shown in (c), the number of the openings 31a is decreased to make the fixation target smaller and presented to the eye E. At this time, it is preferable that the fixation target position display character C is also changed on the television monitor 42 like Ca, Cb, and Cc shown in FIG.
[0017]
FIG. 5 is a flowchart of the control when changing the fixation target presentation position. In step S1, initialization is performed, and in step S2, the fixation target moving switch 44 is input. In the next step S3, in response to the operation of the fixation target moving switch 44, the fixation target opening 31a is moved in an increased number of openings.
[0018]
In step S4, the end of movement of the fixation target is determined. In the case of the end of movement, the number of openings of the fixation target opening 31a is reduced in step S6 so that the same number of openings as before the movement is obtained. If the movement is not finished in step S4, that is, if the movement is continued, the number of openings remains large until the movement is finished in step S5. After the movement is completed, the same number of openings as before the movement is set in step S6. Thereafter, if it is a desired position in step S7, imaging is performed in step S8. If not, the process returns to step S2 again to guide the eye E to the desired position and perform imaging.
[0019]
In the present embodiment, the liquid crystal shutter 31 is used in the fixation target presenting apparatus. However, the size of the fixation target is controlled by controlling the number of light sources to be lit using, for example, a plurality of LED light sources. You may change the length.
[0027]
【The invention's effect】
As described above, the ophthalmologic photographing apparatus according to the present invention presents the fixation target large while the fixation target is moved, and presents the fixation target small, so that the subject does not lose sight of the fixation target. And stable fixation.
[Brief description of the drawings]
FIG. 1 is a configuration diagram.
FIG. 2 is an explanatory diagram of a fixation target.
FIG. 3 is an explanatory diagram of fixation target presentation.
FIG. 4 is an explanatory diagram of an eye observation screen.
FIG. 5 is a flowchart of the operation.
FIG. 6 is a configuration diagram of a conventional example.
FIG. 7 is an explanatory diagram of a conventional eye observation screen.
[Explanation of symbols]
21 Objective lens 22 Perforated mirror 25 Rotating mirror 29 Imaging means 31 Liquid crystal shutters 32 and 35 Light source 41 Control means 42 Television monitor 43 Shooting switch 44 Fixation target moving switch 45 Position detector

Claims (4)

A fixation target presenting means for presenting a fixation target for inducing fixation of the eye to be examined; and a presentation position changing means for indicating a presentation position of the fixation target, the fixation target presenting means including the instruction An ophthalmologic photographing apparatus characterized by changing a size of a fixation target to be presented while moving the fixation target to a fixed fixation target presentation position.   Imaging means for imaging the eye to be examined, conversion means for converting the fixation target presentation position of the fixation target presenting means into an electrical signal, the eye image taken by the imaging means, and the fixation as converted into the electrical signal The ophthalmologic photographing apparatus according to claim 1, further comprising display means for combining and displaying the target presentation position. The ophthalmologic photographing apparatus according to claim 1, wherein the fixation target presenting unit includes a control unit that controls the fixation target presenting position and size .   The ophthalmologic photographing according to claim 1, wherein the fixation target presenting unit changes a size of the fixation target to be presented while moving the fixation target to the instructed fixation target presentation position. apparatus.

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