JPH0119562B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a microphotographic eyepiece lens, particularly a glass plate or liquid crystal plate (hereinafter referred to as a "focal mirror") equipped with a scale, a template, etc., for imprinting a specimen, a scale, a template, etc. together. It relates to a microphotographic eyepiece that can correct the focus when inserted.

In general, in microscopic photography, in order to capture the specimen, scale, template, etc. together, scale,
A glass plate with a template, etc. or a liquid crystal plate capable of displaying scales, templates, etc. is inserted at the imaging position of the objective lens, but the thickness of this glass plate or liquid crystal plate may cause a shift in focus. . Conventional methods to compensate for this focus shift include refocusing using a photographic viewer, and inserting a dummy glass plate or liquid crystal plate into the photographic optical path when scales, templates, etc. are not required. I found a way to keep it. The former method will be explained with reference to FIGS. 1 and 2. In FIG. 1, 1 is a specimen, 2 is an objective lens, 3 is an intermediate image of the specimen 1 by the objective lens 2,
5 is a photographic eyepiece; 5 is a film surface on which an intermediate image 3 is formed by a photographic eyepiece 4; When the focusing mirror 6 is inserted at the position of the intermediate image 3 (see Fig. 2),
Since the intermediate image 3 and the scale of the focusing mirror 6 are formed behind the film surface 5, it is necessary to move the objective lens 2 and perform focusing again. That is, within a certain distance interval,
When a focusing mirror with thickness t and refractive index n is inserted, the optical path length changes by t-t×1/n=(1-1/n)t. Therefore, unless correction is made by extending the optical path length by this length, the object will be out of focus. Furthermore, the method of using a dummy glass plate or liquid crystal plate has the drawback of causing a decrease in resolution.

Therefore, the present invention uses a focusing lens frame compatible with a photographic eyepiece, and uses a step provided in the focusing lens frame to eliminate the need for refocusing when the focusing lens is inserted. To provide a microphotographic eyepiece capable of forming an image of a specimen and a focusing mirror image on a film surface by moving all or part of the individual lenses constituting the photographic eyepiece in the optical axis direction. It is.

The principle of the present invention will be explained below with reference to FIGS. 3 and 4. FIG. 3 shows the case of an external focusing type photographic eyepiece 4', and a display surface 6a for displaying a scale etc.
When a focusing mirror 6 is inserted with the lens on the objective lens side, the photographic eyepiece is moved toward the film surface side in accordance with the thickness of the focusing mirror and the focal length of the photographic eyepiece to perform focusing. FIG. 4 shows the case of an internal focusing type photographic eyepiece, in which when the display surface 6a is placed on the eye lens 8 side and the focusing mirror 6 is inserted, the field lens 7 is moved to the objective lens side to perform focusing.

An embodiment in which the present invention is applied to an internal focusing photographic eyepiece lens is shown in FIG. 5. Reference numeral 11 denotes an eyepiece frame supporting an eye lens 8 at the right end of the figure. Reference numeral 12 denotes a field lens middle frame that is fitted in the eyepiece frame 11 so as to be movable in the optical axis direction and is pressed to the right in the drawing by a spring 13 and supports the field lens 7; 14 is the eyepiece frame 1;
A focusing lens frame that supports a focusing mirror that can be inserted into an opening 11a disposed at a predetermined position of
It is equipped with

Since the embodiment of the present invention is constructed as described above, the focusing lens frame 14 is connected to the opening 11 of the eyepiece frame 11.
When inserted into point a (see FIG. 5B), the field lens middle frame 12 is moved to the left against the spring 13 by the step d, so that the out-of-focus can be corrected. In this case, the amount of movement of the field lens middle frame 12 is determined by selecting the step d corresponding to the thickness of the focusing mirror.

In the above-mentioned embodiment, the case where it is applied to an internal focusing photographic eyepiece is explained, but when applied to an external focusing photographic eyepiece, as is clear from FIG. 3, by inserting a focusing lens frame. Focus is corrected by moving the entire photographic eyepiece toward the film surface. In this case, since the amount of movement of the entire photographic eyepiece varies depending on the thickness of the focusing mirror and the focal length of the photographic eyepiece, a focusing lens frame with a step selected in accordance with these needs to be prepared.

As described above, according to the present invention, by simply inserting the focusing lens frame into the aperture of the photographic eyepiece, the individual lenses that make up the photographic eyepiece are automatically moved by a predetermined amount, thereby correcting the focus shift. Therefore, there is no need to refocus when inserting the focusing lens frame.

In the above explanation, a photographic eyepiece was described, but the present invention can be applied not only to photography but also to projection and observation lenses as long as it is an optical machine that uses a focusing mirror.

[Brief explanation of drawings]

Figures 1 and 2 are diagrams showing the shift in focus due to insertion of a focusing mirror, Figures 3 and 4 are diagrams illustrating the principle of the present invention, and Figure 5 is a diagram showing an embodiment according to the present invention. . 1... Specimen, 2... Objective lens, 3... Intermediate image, 4... Photographic eyepiece, 5... Film surface,
6... Focusing mirror, 6a... Display surface, 7... Field lens, 8... Eye lens, 11... Eyepiece frame, 12... Field lens middle frame, 13...
Spring, 14... Focusing lens frame.

Claims (1)

[Claims] 1. In an optical machine lens that can use a focusing mirror, a core that supports a part of the constituent lens and is fitted in the lens frame so as to be movable in the optical axis direction;
and a pressing means for pressing the middle frame in the direction of the optical axis, the focusing mirror is inserted against the pressing means, and the optical path length shift due to the focusing mirror that occurs when the focusing mirror is inserted is automatically corrected. The focusing mirror includes a step corresponding to the difference in optical path length provided in the lens frame of the focusing mirror in order to move the intermediate frame by a predetermined amount in the optical axis direction against the compression means so as to correct the An optical mechanical lens that may use a focusing mirror.