JP2005087608A - Ophthalmologic photographing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ophthalmologic photographing apparatus easily determining whether a subject closely observes the position of a fixation target presented to the subject. <P>SOLUTION: This ophthalmologic photographing apparatus is characterized in having a frontal eye part observing means observing the frontal eye part of an eye to be examined; a fundus oculi observing means observing a fundus oculi image of the eye to be examined; a changeover means changing over between the frontal eye part observing state by the frontal eye part observing means and the fundus oculi observing state by the fundus oculi observing means; a fixation target presenting means presenting the fixation target guiding the sight line of the eye to be examined; a fixation target highlighting means highlighting the fixation target; an image processing part converting a tone of the observation image; a tone setting part setting the tone conversion for use in the image processing part; and a tone conversion means converting the setting of the tone conversion while highlighting the fixation target by the fixation target highlighting means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ophthalmologic photographing apparatus, and more particularly to an ophthalmologic apparatus such as a fundus camera used in a group examination or the like.

Cardiovascular diseases are mentioned as a characteristic of adult diseases represented by diabetes and hypertension, and fundus photography has been conventionally performed as an inspection method for these diseases. In fundus photography, in order to photograph a desired part, a fixation target is presented to the eye to be examined to guide the subject's gaze, and whether the subject is gazing at the fixation target on the observation screen. Shooting after confirming. With regard to the fixation target, an ophthalmologic apparatus has been proposed in which the fixation target is highlighted to prompt the subject's attention and to ensure fixation (see Patent Document 1 below). .
Japanese Patent Laid-Open No. 11-104085

  However, since the image is originally an infrared image on the observation screen for confirming the state of the fundus oculi to be examined, the image quality is unclear, and in particular, it is difficult to confirm the macular portion displayed as a dark region on the screen. Therefore, even if the fixation target itself is highlighted, it is difficult to confirm whether the subject is gazing at the fixation target, and as a result, an unintentional image may be taken.

  An object of the present invention is to provide an ophthalmologic photographing apparatus that can easily determine whether or not the subject is gazing at the position of the fixation target to be presented to the subject, eliminating the above-described problems.

  In order to achieve the above object, a fundus camera according to the present invention includes an anterior ocular segment observation means for observing the anterior ocular segment of the eye to be examined, a fundus oculi observation means for observing a fundus image of the test eye, and the anterior ocular segment observation means. Switching means for switching between the anterior ocular segment observation state by the fundus observation means and the fundus observation state by the fundus observation means, fixation target presentation means for presenting a fixation target for guiding the gaze of the eye to be examined, and a fixation target for highlighting the fixation target A visual target enhancement unit, an image processing unit that performs gradation conversion of an observation image, and a gradation setting unit that sets gradation conversion used in the image processing unit, and the fixation target enhancement unit determines a fixation target. While highlighting, the gradation conversion setting is changed.

  Further, an anterior ocular segment observation means for observing the anterior ocular segment of the eye to be examined, a fundus oculi observation means for observing a fundus image of the eye to be examined, an anterior ocular segment observation state by the anterior ocular segment observation means, and a fundus oculi by the fundus oculi observation means Switching means for switching the observation state, fixation target presenting means for presenting a fixation target that guides the line of sight of the eye to be examined, fixation target moving means for moving the fixation target, and gradation conversion of the observation image An image processing unit to perform and a gradation setting unit for setting the gradation conversion used in the image processing unit, and the gradation conversion setting is performed while the fixation target moving operation is performed by the fixation target moving unit. It is characterized by changing.

  According to the present invention, while the fixation target is highlighted, the LUT is changed so that the portion of the fundus image displayed on the observation image monitor that has a low input density level, that is, the macula is clearly visible. Therefore, it can be easily determined whether the subject is gazing at the fixation target, and imaging can be performed efficiently.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS The best mode for carrying out the present invention will be described below in detail based on examples with reference to the drawings.

  FIG. 1 shows an apparatus configuration diagram of the present embodiment. On a light path 01 behind an objective lens 1 facing an eye E to be examined, a perforated mirror 2 having a photographing aperture in a hole portion is moved in the direction of the light path 01 and focused. The focus lens 3, the taking lens 4, and the switching mirror 5 that are in the optical path 01 at the time of observation and leave the optical path 01 at the moment of shooting are sequentially arranged. Further, an anterior ocular segment observation lens 6 that is detachable in the optical path 01 is disposed between the objective lens 1 and the perforated mirror 2, and an anterior ocular segment illumination that emits infrared light in the vicinity of the objective lens 1. A light source 7 is arranged.

  A fundus illumination system 8 is disposed on an optical path 02 perpendicular to the optical path 01 of the perforated mirror 2, and the fundus illumination system 8 irradiates the fundus with infrared light during fundus observation and with visible light during fundus photography. It has become.

  A photographing sensor unit 9 is disposed on the optical path behind the switching mirror 5 and connected to the photographed image recording unit 10. The captured image recording unit 10 is connected to a captured image monitor 11.

  A lens 12 and a half mirror 13 are disposed on the optical path in the reflection direction of the switching mirror 5.

  An observation sensor unit 14 is arranged on the optical path in the transmission direction of the half mirror 13 and connected to the observation image processing unit 15. The observation image processing unit 15 is connected to the observation image monitor 16 and the LUT setting unit 17. ing.

  A lens 18 and a fixation target presentation unit 19 for displaying a fixation target are disposed on the optical path in the reflection direction of the half mirror 13. The fixation target presentation unit 19 is connected to a fixation target control unit 20. Yes.

  The fixation target presentation unit 19 includes a backlight and a liquid crystal element in which a plurality of cells as shown in FIG. 2 are arranged in a matrix, and can set transmission / non-transmission of individual cells.

  The control unit 21 includes a switching mirror 5, an anterior ocular segment observation lens 6, an LUT setting unit 17, a fixation target control unit 20, an anterior ocular segment / fundus switching switch 22, a fixation target emphasis switch 23, and a fixation target movement switch 24. , Connected to the photographing switch 25.

  In such a configuration, the photographer first roughly aligns the eye E and the objective lens 1 in the anterior eye observation state.

  In the anterior ocular segment observation state, the anterior ocular segment observation lens 6 is inserted into the optical path 01, the anterior ocular segment illumination light source 7 is turned on, and the switching mirror 5 is disposed in the optical path 01. In this state, the anterior segment image illuminated with infrared light by the anterior segment illumination light source 7 includes the objective lens 1, the anterior segment observation lens 6, the aperture of the perforated mirror 2, the focus lens 3, and the imaging lens 4. The anterior segment image reflected by the switching mirror 5, passing through the lens 12, passing through the half mirror 13, forming an image on the imaging surface of the observation sensor unit 14, and photoelectrically converted by the observation sensor unit 14. The gradation conversion is performed by the observation image processing unit 15 using the LUT set by the LUT setting unit 17 and is displayed on the observation monitor 16. In the anterior eye observation state, it is only necessary to perform approximate alignment. For example, an LUT as shown in FIG. 2 may be used, and the gradation may not be converted.

  The photographer performs alignment by moving a stage portion (not shown) equipped with the optical system shown in FIG. 1 while viewing the anterior eye portion image.

  When the anterior eye / fundus switch 22 is pressed after completing the alignment of the eye E and the objective lens 1 in this manner, the anterior eye illumination light source 7 is detected by the control unit 21 that detects this input. The anterior ocular segment observation lens 6 is retracted out of the optical path 01, and the fundus illumination system 8 emits infrared light. The infrared luminous flux emitted from the fundus illumination system 8 is reflected by the mirror portion around the perforated mirror 2 and illuminates the fundus Er from the pupil Ep via the objective lens 1. The illuminated fundus image passes from the pupil Ep through the objective lens 1, the hole of the perforated mirror 2, the focus lens 3, and the photographing lens 4, is reflected by the switching mirror 5, passes through the lens 12, and passes through the half mirror 13. The fundus image formed on the imaging surface of the observation sensor unit 14 and photoelectrically converted by the observation sensor unit 14 is subjected to gradation conversion by the observation image processing unit 15 using the LUT set by the LUT setting unit 17. The image is displayed on the observation image monitor 16. In the fundus observation state, the optic nerve head shown in FIG. 5 has a high density level (bright), and the macula has a low density level (dark). From the optic nerve head having a high density level to the macula having a low density level. For observation, a linear LUT as shown in FIG. 2 is used, for example. Further, an S-shaped LUT may be used.

  Along with these controls, the control unit 21 turns on the backlight of the fixation target presenting unit 19 via the fixation target control unit 20 and sets only a predetermined cell of the liquid crystal element in a transmissive state to fix the eye E to be examined. Present visual target. As shown in FIG. 3, when the cell set as transmissive is the opening A and the cell set as non-transmissive is the light shielding portion B, the light transmitted through the opening A out of the light emitted from the backlight is It passes through the lens 18, is reflected by the half mirror 13, passes through the lens 12, is reflected by the switching mirror 5, passes through the photographing lens 4, the focus lens 3, the hole of the perforated mirror 2, and the objective lens 1, and passes through the objective lens 1. It reaches the fundus Er from the pupil Ep. That is, the image of the opening A is presented as a fixation target in the dark background to the subject who has arranged the pupil Ep on the optical path 01 of the objective lens 1. Since the fixation target is required to be displayed in a size that determines the line of sight of the subject, for example, the fixation target is presented with four cells as shown in FIG.

  Further, as shown in FIG. 5, the character S indicating the fixation target presentation position to be presented to the subject is synthesized with the fundus image by a character synthesis unit (not shown) and displayed on the observation monitor 16.

  The photographer moves the fixation target presentation position by operating the fixation target movement switch 24 while viewing the fundus image displayed on the observation image monitor 16 and the character S indicating the fixation target presentation position. Then, the visual line of the subject is guided so that a desired part can be imaged. At this time, it is confirmed that the subject is gazing at the fixation target by matching the character S and the macula shown in FIG.

  When the subject has turbidity such as cataracts, or when a known focus target (not shown) is visible to the subject, simply presenting a fixation target as shown in FIG. The subject may have difficulty finding the fixation target.

  In such a case, when the photographer presses the fixation target emphasis switch 23, the control unit 21 that has detected this input causes the LUT setting unit 17 to compare with the LUT in FIG. 2 as shown in FIG. The LUT is set so as to increase the gradation of the low density level portion corresponding to the macula portion. When an S-shaped LUT is used in the fundus observation state, similarly, an LUT is set so as to increase the gradation of a low density level portion corresponding to the macula portion. At the same time, the control unit 21 uses the fixation target control unit 20 as a reference based on the transmission state of the four cells as shown in FIG. 4 and the center of the four cells shown in FIG. 4 as shown in FIG. The fixation target presentation unit 19 is controlled so as to sequentially repeat the enlarged transmission state of the 16 cells for a predetermined time. Then, the control unit 21 resets the LUT setting unit 17 to the LUT as shown in FIG. 7 when the fixed time has elapsed and the highlight display of the fixation target is stopped.

  Thus, when the fixation target is highlighted, the subject's attention is drawn, and the subject can easily find the fixation target. It should be noted that any of the methods described in Patent Document 1 may be used for switch input, fixation target pattern shape, presentation position, and the like when highlighting a fixation target. Furthermore, since the fundus image displayed on the observation image monitor 16 can clearly see the dark part with a low input density level, that is, the position of the macular part, it can be easily determined whether the subject is gazing at the fixation target.

  After the desired imaging region is obtained by the above operation, the photographer presses the imaging switch 25 to perform fundus imaging. When detecting that the photographing switch 25 is pressed, the control unit 21 retracts the switching mirror 5 out of the optical path 01, and at the same time, the fundus illumination system 8 emits a visible flash. This flash light is reflected by the mirror portion around the perforated mirror 2 and illuminates the fundus Er from the pupil Ep via the objective lens 1. The illuminated fundus image passes from the pupil Ep through the objective lens 1, the hole of the perforated mirror 2, the focus lens 3, and the photographing lens 4, and forms an image on the imaging surface of the photographing sensor unit 9. The fundus image photoelectrically converted in (2) is recorded on a memory (not shown) in the captured image recording unit 10 and simultaneously displayed on the captured image monitor 11.

  Note that the photographed image recording unit 10 may record in a storage medium (not shown) or output to a network.

  In the above embodiment, while the fixation target is highlighted, the LUT is changed so that the macular portion having a low density value level is easily seen. However, the fixation target is moved by the fixation target movement switch 24. During operation, the LUT may be changed so that a macular portion having a low density value level can be easily seen.

  In the above-described embodiment, the case where imaging is performed using a separate sensor unit and monitor at the time of observation and imaging of the eye to be examined has been described as an example, but the present invention is not limited thereto, and may be configured to be shared as appropriate. Also good.

  In the above embodiment, the fixation target presentation unit 19 is configured by a backlight and a liquid crystal element in which a plurality of cells are arranged in a matrix. However, a fixation target light source including a plurality of LEDs of different sizes, and You may comprise a fixation target presentation part with the motor etc. which control the position of each fixation target light source.

  In the present invention, most of the above processing can be realized by a program. Therefore, the present invention supplies a system or apparatus with a storage medium storing software program codes for realizing the functions of the above-described embodiments, and the computer (CPU or MPU) of the system or apparatus is stored in the storage medium. Of course, it can also be realized by reading and executing the program code. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention. As a storage medium for supplying the program code, a floppy (R) disk, hard disk, optical disk, magneto-optical disk, CD-ROM, magnetic tape, nonvolatile memory card, ROM, or the like can be used.

Device configuration diagram of the present invention Illustration of LUT Illustration of liquid crystal element Illustration of liquid crystal element Explanatory diagram regarding fixation target presentation on monitor for observation image Illustration of liquid crystal element Illustration of LUT

Explanation of symbols

01, 02 Optical path 1 Objective lens 2 Perforated mirror 3 Focus lens 4 Shooting lens 5 Switching mirror 6 Anterior ocular segment observation lens 7 Anterior eye illumination light source 8 Fundus illumination system 9 Shooting sensor unit 10 Captured image recording unit 11 Captured image Monitor 12 lens 13 half mirror 14 observation sensor unit 15 observation image processing unit 16 observation image monitor 17 LUT setting unit 18 lens 19 fixation target presentation unit 20 fixation target control unit 21 control unit 22 anterior eye / fundus switching Switch 23 fixation target emphasis switch 24 fixation target movement switch 25 photographing switch A opening B light-shielding part E eye to be examined Ep pupil Er fundus

Claims (2)

  An anterior ocular segment observation means for observing the anterior ocular segment of the eye to be examined, a fundus oculi observation means for observing a fundus image of the eye to be examined, an anterior ocular segment observation state by the anterior ocular segment observation means, and a fundus oculi observation state by the fundus oculi observation means Switching means for switching, fixation target presenting means for presenting a fixation target for guiding the line of sight of the eye to be examined, fixation target enhancement means for highlighting the fixation target, and image for gradation conversion of the observation image A gradation setting unit for setting gradation conversion used in the processing unit and the image processing unit, and the gradation conversion setting is changed while the fixation target is highlighted by the fixation target enhancement unit. An ophthalmologic photographing apparatus characterized by that.   An anterior ocular segment observation means for observing the anterior ocular segment of the eye to be examined, a fundus oculi observation means for observing a fundus image of the eye to be examined, an anterior ocular segment observation state by the anterior ocular segment observation means, and a fundus oculi observation state by the fundus oculi observation means Switching means for switching, fixation target presenting means for presenting a fixation target that guides the line of sight of the eye to be examined, fixation target moving means for moving the fixation target, and image for gradation conversion of the observation image A gradation setting unit configured to set gradation conversion used in the processing unit and the image processing unit, and the gradation conversion setting is changed while the fixation target moving unit is moving the fixation target. An ophthalmologic photographing apparatus characterized by that.