JPS618024A - Position matching optical apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a positioning device that can be widely applied to ophthalmological optical instruments such as ophthalmic YAG laser devices and fundus cameras, as well as optical instruments for general measurement, photography, and treatment. This invention relates to an optical device.

Conventional alignment optical devices of this type are generally designed to minimize the spot diameter of the light beam during focusing, but the focus position is generally not very clear and vignetting occurs. It also has the disadvantage of being difficult to understand.

Also, a type in which the prism is rotated by a motor is known, but this type has the drawbacks of a complicated structure and high cost.

An object of the present invention is to provide an alignment optical device that allows the focus position to be clearly confirmed with a relatively simple configuration, and that also makes it easy to distinguish vignetting.
Its gist is that it is an optical device that matches the relative positional relationship between the object and the device by observing the alignment light projected onto the object. This feature is characterized by the insertion of a shutter that sequentially opens a portion of the screen.

The present invention will be explained in detail based on illustrated embodiments.

FIG. 1 shows an embodiment in which the present invention is applied to an ophthalmological YAG laser device, where 1 is a first light source, a therapeutic YAG laser light source, and therapeutic light L1 emitted from this light source 1 is transmitted through a lens 2. 3, the light beam is expanded, reflected by a light splitting member 4.5, and condensed by an objective lens 6 to illuminate the target eye E. On the other hand, the alignment light L2 emitted from the alignment light source, which is the second light source 7 using a He-Ne laser, is expanded in luminous flux by a lens 8.9, passes through the light splitting member 4, and is further split into light beams. It is reflected by the member 5 and guided to the target eye E. Furthermore, the observation eye e of the patient can observe the target eye E through the observation optical system 10.11. A shutter 12 is inserted into the optical path of the alignment light L2, and is configured to sequentially open a portion of the shutter in the circumferential direction with respect to the optical axis. FIG. 2 shows an example of this shutter 12, which includes four elements 12a, 12
12b, 12c, and 12d, and has a structure in which these elements 12a to 12b are successively opened by an applied voltage from a control circuit (not shown).

The treatment light L1 emitted from the first light source 1 and the second light source 7
It is designed to be focused at the same position as the alignment light L2 emitted from the , and when this focus is to be adjusted, instead of moving the entire device, it is necessary to move a member such as the objective lens 6 that has a common optical path. You can also focus by
- Figures 3 (a) and (b) show the state when the alignment light L2 from the second light source 7 is projected onto the target eye E, and (a) shows the case where the focus is shifted. , (b) shows the case where the image is in focus. That is, when the focus is shifted, the light incident from the elements 12a, 12b, 1, 2c, 12d will be transmitted to A1, B1, . C1,
Dl, and these appear to blink sequentially, but when the focus is correct, as shown in Figure 3(b), the light beams incident from elements 12a-12d coincide, and the blinking is not visible. .

Now, if the target eye E is slightly shifted and the iris Ea or @Eb eclipses a part of the luminous flux, for example, the luminous flux that has passed through element 12d in Fig. 2, then in this state the light will blink even though it is in focus. Become. The temporal change in luminous intensity in this case is shown in FIG. Here, A2, B2, C2 are elements 12a
, 12b, 12c, and C2 is element 1.
Since the light that should have passed through 2d is blocked, the light in that area appears to be missing or flickering.

FIG. 5 shows another example of the shutter 12, in which the light beam L2 emitted from the second light source 7 for positioning is split into two by a prism 13.
The shutter blades are divided and alternately shut off by semicircular shutter blades 15 as shown in FIG. 6, which are rotated by a motor 14, and the same effect as in the previous example can be obtained.

Although the above embodiments are applied to a YAG laser device for ophthalmologic treatment, it goes without saying that the present invention can also be widely applied to imaging devices such as fundus cameras, measuring devices, and the like.

As explained above, the alignment optical device according to the present invention has a relatively simple configuration in which a shutter is provided that sequentially opens a part of the circumferential direction with respect to the optical axis of the optical path of the alignment light. You can clearly know the focus position,
This method has the advantage that it is easy to accurately match the relative positional relationship between the object and the device, and even if vignetting occurs, it can be clearly recognized.

[Brief explanation of drawings]

The drawings show an embodiment of the alignment optical device according to the present invention, and FIG. 1 is an optical layout diagram in which the present invention is applied to a laser device for ophthalmic treatment, and FIG. 2 is a front view of a shack.
Figures 3 (a) and (b) are illustrations of the alignment light when out of focus and in focus; Figure 4 is an illustration of temporal changes in the alignment light when vignetting occurs; FIG. 5 is another configuration diagram of the shutter, and FIG. 6 is a front view of the shutter blade. 1 is a first light source, 4.5 is a light splitting member, 6 is an objective lens, 7 is a second light source, 10.11 is an observation optical system, 12
is a shutter, 13 is a prism, 14 is a motor, and 15 is a shutter blade. Patent applicant: Canon Co., Ltd. Figure 1, Figure M3. Figure 5

Claims (1)

[Claims] 1. An optical device that matches the relative positional relationship between the object and the device by observing the alignment light projected onto the object, the optical device including a light beam in the alignment optical path relative to the optical axis. 1. An optical device for positioning, characterized in that a shutter is inserted to sequentially open a portion of the circumference in a circumferential direction. 2. The positioning optical device according to claim 1, wherein the shutter is constituted by a liquid crystal consisting of a plurality of elements that open sequentially. 3. The positioning optical device according to claim 1, wherein the shutter includes shutter blades that alternately block a plurality of positioning lights divided by a prism and a motor that drives the shutter blades.