JP4744870B2 - Ophthalmic imaging equipment - Google Patents

Description

The present invention relates to an ophthalmic photographing apparatus such as a fundus camera using a lighting device in which a plurality of light emitting diodes.

  Conventionally, in a fundus camera, alignment or focus adjustment is performed by irradiating the fundus of the subject's eye with illumination light from an illumination light source such as a halogen lamp through a ring slit, and then emitting a strobe. Then, photographing the fundus is performed (Patent Document 1).

  There is also known a fundus camera that uses the observation light source and the photographing light source as the same light source, and observes and photographs the fundus by changing the light source light amount during observation and during photographing (Patent Document 2).

In the fundus camera, it is preferable to use a light source that instantaneously turns on and off the light emission and does not generate afterglow as the illumination light source, and a light emitting diode is suitable as such a light source. Illuminating devices using light emitting diodes include, for example, an illuminating device in which light emitting diodes are arranged in a ring shape (Patent Document 3), and an illuminating device that illuminates light emitting diodes of different colors through a diffusion plate (Patent Document 4). Are known.
JP 2003-325456 A Japanese Patent Laid-Open No. 5-285112 JP 2003-179265 A JP 11-295047 A

  However, the fundus camera requires a mechanism for inserting and removing various filters depending on the shooting mode, and the optical system becomes complicated (Patent Document 1). In order to make the same, the amount of light had to be changed instantaneously in observation and photographing, and there was a problem that a complicated electric circuit was required to adjust the amount of light.

  Moreover, when using the illuminating device which arranged the light emitting diode as an illuminating device, in the illuminating device which is seen by patent document 3, since only a single luminescent color is obtained and each light emitting diode cannot be controlled individually, The light quantity cannot be increased or decreased by thinning light emission, and it is difficult to control the light quantity. In addition, the illumination device as disclosed in Patent Document 4 has a problem in that light from a light emitting diode of a different color is transmitted through the diffuser plate, causing a light amount loss due to the diffuser plate transmission.

The present invention, such problems has been made to solve the, to provide an ophthalmic photographing apparatus capable of performing with the color adjusting light quantity control of the light source is a common and irradiation Meiko source imaging light source Is the subject.

The ophthalmologic photographing apparatus of the present invention (Claim 1)
A plurality of light emitting diodes which form the illumination light of the white and infrared light, an illumination device equipped with an opening for transmitting light from said light emitting diodes as the illumination light,
Light emission control means for controlling light emission of the light emitting diode of the illumination device so that infrared illumination light can be obtained during fundus observation, and white illumination light can be obtained during fundus photography. ,
During fundus observation, the fundus is illuminated with infrared illumination light, and during fundus photography, the fundus is illuminated with white illumination light to photograph the fundus .

The ophthalmologic photographing apparatus of the present invention (Claim 2 )
A lighting device comprising red, green and blue light emitting diodes, and an opening for transmitting light from the light emitting diodes as illumination light ;
A light emission control means for controlling light emission of the light emitting diode of the illuminating device so that dimmed white illumination light can be obtained during fundus observation, and white light that has been increased during fundus photography; Have
When observing the fundus, the fundus is illuminated with white illumination light that is dimmed, and when photographing the fundus, the fundus is illuminated with white illumination light that is increased in brightness to photograph the fundus .
The ophthalmologic photographing apparatus of the present invention (Claim 3)
A lighting device comprising red, green and blue light emitting diodes, and an opening for transmitting light from the light emitting diodes as illumination light;
Light emission control means for controlling the light emission of the light emitting diode of the illumination device so that blue illumination light can be obtained during fundus observation and bright white illumination light can be obtained during fundus photography. ,
During fundus observation, the fundus is illuminated with blue illumination light, and during fundus photography, the fundus is illuminated with white illumination light that has been brightened to photograph the fundus .

Moreover, the ophthalmologic photographing apparatus of the present invention (claim 6 )
A concave diffuse reflector, a plurality of light emitting diodes that form white and infrared illumination light disposed toward the diffuse reflector, and light from the light-emitting diode diffusely reflected by the diffuse reflector A first lighting device including an opening that transmits light as illumination light;
A concave diffuse reflector, red, green and blue light emitting diodes arranged toward the diffuse reflector, and an opening for transmitting light from the light emitting diode diffusely reflected by the diffuse reflector as illumination light; A second lighting device comprising:
Selection means for selecting the first and second illumination devices according to the shooting mode;
Light emission control means for selectively lighting the light emitting diodes of the first and second lighting devices or controlling the light quantity of the light emitting diodes to be lit;
An image sensor for imaging the fundus illuminated with illumination light from the first or second illumination device;
And a recording apparatus for recording fundus image captured,
The first lighting device and the second lighting device are separate lighting devices, respectively .

In the ophthalmologic photographing apparatus according to the present invention , the amount of light can be increased or decreased instantaneously, and both the illumination light source and the photographing light source can be provided, so that the illumination optical system can have a simple configuration.

  The present invention relates to an illuminating device using a light emitting diode and an ophthalmologic photographing apparatus using the illuminating device, and the ophthalmic photographing apparatus performs color photographing of the fundus (mydriatic photographing, non-mydriatic photographing), visible fluorescent photographing. It is configured as a fundus camera that can. In the following, the present invention will be described in detail based on embodiments shown in the drawings.

  In FIG. 1, the fundus camera is provided with illumination devices 1 and 11, and one of them is selected and used for illumination of the fundus. The illuminating device 1 is mainly used for non-mydriatic color photographing, and the illuminating device 11 is used for mydriatic color photographing, visible fluorescent photographing or the like.

  The light emitted from the illumination device 1 or 11 is reflected by the relay lens 20, the black dot plate 21 for removing the reflection of the objective lens, the relay lens 22, and the perforated total reflection mirror 23 having a hole in the center and then the objective. The light enters the fundus Er from the pupil Ep of the eye E through the lens 24 and illuminates the fundus Er.

  The reflected light from the fundus Er is again received from the pupil Ep through the objective lens 24, passes through the focusing lens 26 and the imaging lens 27 through the hole of the perforated total reflection mirror 23, and returns to the return mirror 28. Incident. The light reflected by the return mirror 28 is subsequently reflected by the return mirror 29 and enters the finder (eyepiece lens) 30. The examiner observes the fundus through the finder 30 and performs alignment and focus adjustment. Can do.

  When the return mirror 29 is removed from the optical path, the light reflected by the return mirror 28 passes through the field stop 31 and the field lens 32, and then is reflected by the mirror 33 and then passes through the lens 34, and is sensitive to infrared light. Is incident on an infrared CCD (imaging device) 35, and a fundus image is captured by the infrared CCD 35. The fundus image captured by the infrared CCD 35 is displayed as a moving image on the monitor 52 via the switch 51 operated by the monitor switching circuit 50, and the examiner can perform alignment and focus adjustment while observing this image. it can.

  When the return mirror 28 leaves the optical path, the fundus image is captured by a color CCD (imaging device) 36 that is sensitive to visible light, and the captured fundus image is recorded in the still image recording device 37. The fundus image recorded in the still image recording device 37 can be displayed on the monitor 52 when the monitor switching circuit 50 switches the switch 51 to the position indicated by the dotted line. Since the monitor switching circuit 50 switches the switch 51 according to the time set by the display time setting circuit 44, the fundus moving image from the infrared CCD 35 or the still image of the fundus photographed by the color CCD 36 according to the time. Is displayed on the monitor 52.

  A visible fluorescent barrier filter 25 inserted in the optical path at the time of visible fluorescent photographing is detachably disposed in the optical path between the perforated total reflection mirror 23 and the focusing lens 26.

  Further, the fundus camera is provided with a control circuit (control means) 40 comprising a CPU or the like. The control circuit 40 includes a signal indicating the photographing mode set by the photographing mode setting means 42, and a signal from the photographing switch 41. Based on these signals, the control circuit 40 switches the illumination devices 1 and 11 as will be described later, and the light emitting diodes disposed in the illumination device 1 or 11 via the LED light emission control means 43. Selective lighting and the light quantity of the light emitting diode to be lit are increased or decreased. In addition, the control circuit 40 controls insertion / removal of the return mirrors 28 and 29 and the visible fluorescent barrier filter 25 and switches the switch 51 via the display time setting circuit 44 and the monitor switching circuit 50.

  FIG. 2A shows a detailed configuration of the lighting device 1. The lighting device 1 has a substantially hemispherical concave substrate 2, and the concave surface of the substrate 2 has a high reflectivity. A diffuse reflector 3 is attached. The substrate 2 is formed by molding a metal plate or resin, and the concave diffusive reflector 3 increases the reflectivity by applying a thin film treatment to the aluminum mirror surface (the reflectivity is about 95%), and on the surface. This is a reflecting plate or a reflecting film in which minute irregularities made of an assembly of minute equilateral triangles (polygons of a 3D surface image) are formed to cause irregular reflection to improve diffusibility.

  Also, three ring slits 4, 5, and 6 are attached to the upper portion of the substrate 2, and the ring slit 4 includes a light shielding portion 4a provided at the center of the transparent plate and a peripheral portion as shown in FIG. A ring-shaped light-shielding portion 4b is provided, and a space between the light-shielding portions 4a and 4b is a ring-shaped opening (light transmission portion) 4c, and the lower surface of each light-shielding portion 4a and 4b, that is, the diffuse reflector 3 A large number of light emitting diodes are arranged on the opposite side.

  An example of the arrangement is shown in FIG. 3, and a rectangular area 8 indicated by a dotted line is formed in the light shielding portion 4a. In this area 8, a large number of light emitting diodes are regularly arranged. ing. An example of the arrangement is schematically shown in the lower part of FIG. 3, and the arrangement of the light emitting diodes in this region is one red (R) light emitting diode 7a and two white (W) light emitting diodes 7b. 7c and one green (G) light emitting diode 7d as a group, and the same number of groups are arranged in the vertical and horizontal directions. The ratio of the total number of white (W), red (R), and green (G) light emitting diodes in this region 8 is 2: 1: 1, and the wavelength distribution of the white light emitting diodes has a peak in blue. However, since red is scarce (almost), a balanced white light source can be obtained by setting the above ratio and causing each light emitting diode to emit light uniformly with the same luminance.

  In addition, in the region of the light shielding portion 4a outside the region 8, four infrared light emitting diodes 7e are arranged at equal intervals along each side of the region 8, and the light emitting diode is disposed in the light shielding portion 4b. Groups of 7a to 7d are arranged at equal intervals in the circumferential direction, and infrared light emitting diodes 7e (one in the illustrated example) are arranged between the groups.

  Further, above the ring slit 4, a ring slit 5 having a circular opening (light transmitting portion) 5a at the center of the transparent plate and a ring-shaped light shielding portion 5b at the periphery is attached. A ring slit 6 comprising a circular light-shielding portion 6a provided at the center of the transparent plate, a peripheral ring-shaped light-shielding portion 6b, and a ring-shaped opening (light transmission portion) 6c between the light-shielding portions 6a and 6b is attached. The openings 4c, 5a, and 6c that transmit the light of each ring slit have such a size and shape that reflected light from the diffuse reflector 3 escapes upward as illumination light. When the illumination device 1 is used in the fundus camera of FIG. 1, the ring slit 4 is attached to the corneal conjugate position, the ring slit 5 is attached to the pupil conjugate position, and the ring slit 6 is attached to the crystalline lens conjugate.

  The illuminating device 1 is used for non-mydriatic color imaging, and the illuminating device 11 shown in FIG. 2B is used for mydriatic color imaging or visible fluorescence imaging. The illuminating device 11 is different from the illuminating device 1 in the size of the opening of the ring slit, the type of light emitting diode used, and the arrangement thereof. The substrate 12, the diffuse reflector 13, and the ring slit 14 are different. The light shielding portions 14a and 14b and the opening portion 14c have the same shape and material as the light shielding portions 4a and 4b of the ring slit 4 and the opening portion 4c, respectively.

  In the illuminating device 11, as shown in FIG. 4, in the rectangular area 18 of the light shielding portion 14a, one red (R) light emitting diode 17a, two green (G) light emitting diodes 17b and 17c, and 1 The blue (B) light emitting diodes 17d are grouped, and light emitting diodes in a matrix arrangement are provided in which the same number of the groups are arranged in the vertical and horizontal directions. In the light shielding part 14b, groups of the light emitting diodes 17a to 17d are arranged at equal intervals in the circumferential direction.

  Moreover, in the illuminating device 11, the diameter D <b> 2 of the opening 15 a of the ring slit 15 is larger than the diameter D <b> 1 of the opening 5 a of the illuminating device 1. It is larger than the above, and can increase the amount of illumination of the fundus. Similarly to the illumination device 1, the ring slit 14 is attached to the cornea conjugate position, the ring slit 15 is attached to the pupil conjugate position, and the ring slit 16 is attached to the crystalline lens conjugate.

  Next, photographing performed by the fundus camera configured as described above will be described.

  When non-mydriatic photographing is set by the photographing mode setting means 42, the control circuit 40 inserts the illumination device 1 into the optical path, and causes the visible fluorescent barrier filter 25 and the return mirror 29 to leave the optical path. Then, the light emitting diodes 7a to 7d of the illumination device 1 are turned off via the LED light emission control means 43, and the infrared light emitting diode 7e is turned on. Thereby, the illuminating device 1 emits infrared light, and the infrared light diffused and diffused by the diffuse reflector 3 having a high reflectivity is incident on the eye E through the illumination optical system from the opening, The fundus Er is illuminated uniformly with infrared light. The reflected light from the fundus is reflected by the return mirror 28 and then enters the infrared CCD 35, and an infrared fundus image is captured. Since the captured fundus image is displayed as a moving image on the monitor 52 via the switch 51, the examiner performs alignment and focus adjustment while observing the fundus image.

  When the alignment and focus adjustment are completed, the photographing switch 41 is pressed, so the control circuit 40 turns off the infrared light emitting diode 7e via the LED light emission control means 43 and turns on all the light emitting diodes 7a to 7d. Thereby, the illuminating device 1 becomes a white light source, and the fundus is illuminated with white light. At this time, since the return mirror 28 is separated from the optical path, the fundus image is captured by the color CCD 36 and recorded in the recording device 37 as a still image. The recorded fundus image can be displayed on the monitor 52 because the switch 51 is switched to the recording device 37 side by the monitor switching circuit 50 for the time set by the display time setting means 44.

  As described above, the wavelength distribution of the white light emitting diodes 7b and 7c has a peak in blue, almost no red, and the ratio of the number of white, red and green light emitting diodes is 2: 1: 1. Therefore, balanced white light can be obtained by causing each light emitting diode to emit light uniformly with the same luminance. In this case, if it is desired to enhance redness, the light emission amount of the white (W) and green (G) light emitting diodes 7b, 7c and 7d is reduced by the LED light emission control means 43, and the light emission amount of the red (R) light emitting diode 7a. If the blue light intensity is to be increased, the light emission amount of the green (G) light-emitting diode 7d and the red (R) light-emitting diode 7a is decreased, and the light emission amounts of the white (W) light-emitting diodes 7b and 7c are increased. . By controlling the light amount of each light emitting diode in this way, it is possible to adjust the hue while keeping the entire light emission amount constant, and it is possible to photograph a good fundus image.

  The illumination state of the illumination device at the time of non-mydriatic photographing using the above illumination device 1 is shown in the upper column of FIG.

  On the other hand, when the mydriatic photographing is set by the photographing mode setting means 42, the illumination device 11 is inserted into the optical path, and during observation, the red light emitting diode 17a, the green light emitting diodes 17b and 17c, and the blue light emitting diode 17d are thinned and lit. Therefore, the fundus is illuminated with white light with a small amount of light. When the fundus is observed through the viewfinder 30 and the alignment and focus adjustment are completed, the photographing switch 41 is operated. At this time, all red, green and blue light emitting diodes are turned on by the LED light emission control means 43, so that the fundus is illuminated with the increased white light, and the return mirror 28 is synchronized with the operation of the photographing switch 41. Since it leaves the optical path, the fundus is imaged by the color CCD 36.

  When visible fluorescent photographing is set, the blue light emitting diode 17d is turned on and the fundus is illuminated with blue illumination light. When a fluorescent agent is injected intravenously, visible fluorescence is generated in the fundus by this blue illumination light. As in the case of mydriatic photographing, the fundus is observed through the viewfinder 30, and when the alignment and focus adjustment are completed, the photographing switch 41 is operated. At this time, as in mydriatic photography, all the red, green and blue light emitting diodes are turned on by the LED light emission control means 43, so that the fundus is illuminated with the increased white light. Further, in synchronization with the operation of the photographing switch 41, the visible fluorescence barrier filter 25 is inserted and the return mirror 28 is detached from the optical path, so that a visible fluorescence image of the fundus is captured by the color CCD 36.

  The fundus image captured by the color CCD 36 at the time of mydriatic photographing and visible fluorescent photographing is recorded and stored in the recording device 37 as in the case of non-mydriatic photographing, and the switch 51 is switched to the upper side in FIG. When recorded, the recorded image can be displayed on the monitor 52.

  Further, since the illumination device 11 can select the color of the light source, the green light emitting diodes 17b and 17c can be turned on to perform red-free imaging for diagnosing a lesion such as a blood vessel.

  The illumination state when this illumination device 11 is used is shown in the lower column of FIG.

  In addition, in the illuminating device 1, a blue light emitting diode can also be used instead of using a white light emitting diode. In that case, the matrix arrangement is changed depending on the luminance of the light emitting diode to be used. For example, when the luminance of the blue and red light emitting diodes is equal and both are higher than the luminance of the green light emitting diode (B = R> G), the green light emitting diode is disposed instead of the white light emitting diode. This makes it easier to balance the whole. The advantage in this case is that the selection range of the spectral distribution of the light emitting diode to be selected is widened. When white light emitting diodes are used, the main purpose of light emitting diodes of other colors is to correct non-uniformity of white distribution.

  Moreover, you may make it use the arrangement | sequence shown in FIG. 6 regarding the arrangement | sequence of the light emitting diode of the illuminating device 1. FIG. In this example, the arrangement of the light emitting diodes in the rectangular region 8 of the light-shielding portion 4a is such that red (R), green (G), and blue (B) light emitting diodes are grouped as shown by reference numerals 8a and 8b. 8a is arranged in the horizontal direction, groups 8b are arranged in the same number in the vertical direction, and yellow (Y) light-emitting diodes that are insufficient in three colors are arranged between the groups. Also, the same number of groups 8a and 8b are alternately arranged in the circumferential direction with respect to the peripheral light-shielding portion 4b. Also in this example, by controlling the light amount of each light emitting diode, an illumination device capable of adjusting the hue while keeping the entire light emission amount constant can be obtained as in the example shown in FIG.

  In FIG. 1, an image sensor similar to the color CCD 36 can be used instead of the finder 30. In this case, the image of the image sensor is guided to the monitor 52 and the fundus image is observed on the monitor 52. Make alignment and focus adjustments.

  As mentioned above, although the Example of this invention was described, this invention is not limited to these Examples, Various application examples can be considered. For example, infrared light and red, green, and blue colors are arranged in the same illumination device, and the ring slit size is made variable to switch between non-mydriatic / mydriatic photography without switching the illumination device. It is also possible.

It is the block diagram which showed the structure of the ophthalmic imaging device of this invention. It is the longitudinal cross-sectional view which showed the structure of the illuminating device. It is the figure which looked at the illuminating device of FIG. 2 (A) from the A direction, and is explanatory drawing which showed the arrangement | sequence of a light emitting diode. It is the figure which looked at the illuminating device of FIG.2 (B) from the A direction, and is explanatory drawing which showed the arrangement | sequence of a light emitting diode. It is the table | surface explaining the illumination state of the illuminating device according to the imaging | photography mode in the ophthalmologic imaging device of FIG. It is explanatory drawing which showed the other example of arrangement | sequence of a light emitting diode.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 11 Illumination device 7a-7e Light emitting diode 17a-17d Light emitting diode 30 Finder 35 Infrared CCD
36 color CCD
40 control circuit 42 photographing mode setting means 41 photographing switch 43 LED light emission control circuit

Claims (9)

A plurality of light emitting diodes which form the illumination light of the white and infrared light, an illumination device equipped with an opening for transmitting light from said light emitting diodes as the illumination light,
Light emission control means for controlling light emission of the light emitting diode of the illumination device so that infrared illumination light can be obtained during fundus observation, and white illumination light can be obtained during fundus photography. ,
An ophthalmologic photographing apparatus that illuminates the fundus with infrared illumination light during fundus observation and illuminates the fundus with white illumination light during fundus photographing. A lighting device comprising red, green and blue light emitting diodes, and an opening for transmitting light from the light emitting diodes as illumination light ;
A light emission control means for controlling light emission of the light emitting diode of the illuminating device so that dimmed white illumination light can be obtained during fundus observation, and white light that has been increased during fundus photography; Have
An ophthalmologic photographing apparatus that illuminates the fundus with white illumination light dimmed during fundus observation and illuminates the fundus with white illumination light increased in fundus photographing . A lighting device comprising red, green and blue light emitting diodes, and an opening for transmitting light from the light emitting diodes as illumination light;
Light emission control means for controlling the light emission of the light emitting diode of the illumination device so that blue illumination light can be obtained during fundus observation and bright white illumination light can be obtained during fundus photography. ,
An ophthalmologic photographing apparatus that illuminates the fundus with blue illumination light during fundus observation and illuminates the fundus with white illumination light that increases the fundus during photographing . 4. The ophthalmologic photographing apparatus according to claim 1, wherein light from the light emitting diode is diffusely reflected through a diffuse reflector . 5. The opening is a ring-shaped opening, and both sides of the ring-shaped opening are light-shielding parts, and light-emitting diodes are regularly arranged in each light-shielding part or any one of the light-shielding parts. The ophthalmologic photographing apparatus according to claim 1, wherein the ophthalmologic photographing apparatus is characterized . A concave diffuse reflector, a plurality of light emitting diodes that form white and infrared illumination light disposed toward the diffuse reflector, and light from the light-emitting diode diffusely reflected by the diffuse reflector A first lighting device including an opening that transmits light as illumination light;
A concave diffuse reflector, red, green and blue light emitting diodes arranged toward the diffuse reflector, and an opening for transmitting light from the light emitting diode diffusely reflected by the diffuse reflector as illumination light; A second lighting device comprising:
Selection means for selecting the first and second illumination devices according to the shooting mode;
Light emission control means for selectively lighting the light emitting diodes of the first and second lighting devices or controlling the light quantity of the light emitting diodes to be lit;
An image sensor for imaging the fundus illuminated with illumination light from the first or second illumination device;
A recording device for recording the imaged fundus image;
With
An ophthalmologic photographing apparatus, wherein the first illumination device and the second illumination device are separate illumination devices. The first lighting device is selected during non-mydriatic photographing, the infrared light for the observation, at the time of shooting, the claims as white light is obtained, the light emission of the light emitting diode is characterized in that it is controlled 6 The ophthalmologic photographing apparatus described in 1. The second illuminating device is selected at the time of mydriatic imaging so that a dimmed white illumination light can be obtained at the time of observation, and an increased white light can be obtained at the time of imaging. The ophthalmologic photographing apparatus according to claim 6 , wherein light emission is controlled. The second illumination device is selected at the time of fluorescent photographing, and the light emission of the light emitting diode is controlled so that blue illumination light can be obtained at the time of observation, and bright white light can be obtained at the time of photographing. The ophthalmologic photographing apparatus according to claim 6 .