JPH03168622A - Camera incorporating filter - Google Patents

Abstract

PURPOSE:To perform excellent portrait photographing even by a fixed focus camera by moving the focusing position of a photographing optical system to a short distance side at the time of using a filter. CONSTITUTION:A lens barrel 2 holding a photographing lens 1 is always energized backward in an optical axis direction by an elastic member. Dowels 7a and 7b are fitted in the hole part 2a and the groove part 2b of the lens barrel 2 so that they can freely slide and the lens barrel 2 is extended to a front side by turning an extension cam ring 3. By moving a filter switching lever 5 in a right direction in the case of using the filter, the filter 4b advances in the optical path of the lens 1 and a filter holding member 4 turns counterclockwise and the cam ring 3 turns clockwise. Then, the focusing position obtained by extending the lens barrel 2 forward by a specified quantity is changed to the short distance side and the excellent portrait photographing is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a camera having a filter that can be inserted into and taken out of a photographing optical system.

BACKGROUND ART Conventionally, various cameras have already been devised that have built-in filters that can be taken in and out of photographic optical systems.

Problems to be Solved by the Invention> By the way, many of the filters in the conventional examples mentioned above are mainly for the purpose of photographing portraits of people, such as soft focus filters and filters that blur the periphery of the screen.

On the other hand, if the camera is a fixed focus camera, the F number of the lens is generally F4.5 and the lens focal length is about 351, and the focal position is set so that it is just in focus when the subject distance is 3 m. Due to the depth of field, it is possible to photograph objects from approximately 1.5 meters to infinity.

However, when the subject distance is about 1.5 meters, the focus is actually poor, and this type of camera is not very suitable for portraits of people who are photographed at close range with many machines. there were.

Portrait photography is generally done at close range, and the focal length of the withdrawal lens is 35mm.
If the distance to the subject is 10 meters or more, it is almost never photographed with am+, because at such a distance, the subject becomes only a small silver shadow, resulting in a so-called small-sized photograph.

SUMMARY OF THE INVENTION In view of the problems of the prior art described above, it is an object of the present invention to provide a camera with a built-in filter that can focus on short distances better than on long distances during portrait photography.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the present invention provides a filter that is movable between a first position that enters the photographing optical path and a second position that retreats outside the photographic optical path. In a camera with a built-in filter, the focal position of the photographing optical system consisting of a photographing lens or a conveyor lens and a filter is different when the filter is in the first position and in the second position.

Further, the filter has its own optical power, and it is effective that the focal position of the photographing optical system is closer to the short distance side when the filter is in the first position than when it is in the second position. be.

Further, it is preferable that the filter is suitable for portrait photography, such as a center image filter or a soft focus filter.

Effects> The camera with a built-in filter configured as described above can cover the usual subject distance during portrait projection by automatically shifting the focus to the short distance side when using the filter in the first position.

In addition, by providing the filter with its own optical power and using that power to move the focal point toward the short distance side, it is possible to make the filter suitable for bonitrate imaging without increasing costs.

Also, soft focus and center. - A filter suitable for portrait photography with effects such as images enters the photographing optical path (first position) and retreats out of the optical path (second position).
For example, when the filter is in the photographing optical path, the focal position of the photographing optical system is changed in conjunction with the position of It is possible to make the focus camera suitable for portrait photography as well.

Embodiment> An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

Figure 1 shows when the filter is not in use (the second position of the filter).
FIG. 2 shows the filter in use (the first position [) of the filter.

In the figure, 1 is a projection lens, 2 is an 11 cylinder holding the photographing lens 1, which is urged backward in the optical axis direction by an elastic member (not shown), and is provided parallel to the optical axis direction. Dowels 7a are installed on the base plate (not shown) in the hole 2a and the groove 2b.
and 7b are slidably fitted to each other. Reference numeral 3 denotes a feeding cam ring, which is attached to a base plate (not shown) so as to be rotatable around the optical axis, has a cam surface (not shown), and biases the lI cylinder 2 by rotating clockwise. It is designed to move forward against the force.

Reference numeral 4 denotes a filter support member, which is attached to a base plate (not shown) so as to be rotatable about a shaft 4a, and has a filter 4 attached to one end thereof.
The filter 4b is a portrait filter having a soft focus effect or a center image effect.

Further, the filter support member 4 has an elongated hole 4C in the middle portion and a dowel 4d at the other end, and the elongated hole 4C is slidably fitted into the dowel 3a provided upright on the feeding cam ring 3. ing. 5 is a filter switching lever, and its elongated holes 5a, 5
b is fitted with dowels 7c and 7d erected on the base plate (not shown) so as to be slidable in the left-right direction in the figure, and a groove 5C provided between the elongated holes 5a and 5b is fitted with the dowel 4d of the filter support member 4. They are slidably fitted together and are biased toward the left in the figure by a spring 6. The range of movement of the filter support member 4 in the left and right direction is limited by a stopper 7e installed upright on the base plate (not shown).
It is regulated w1 by 7f.

In this embodiment with the above structure, when the filter shown in FIG. 1 is not in use, the filter 4b is retracted out of the imaging optical path of the photographic lens 1, and in this state, the imaging lens 1 moves from a certain short distance to infinity. It is located in a position that allows photographing with a confusing inner diameter that does not pose a practical problem.

When using the filter shown in FIG. 2, the filter switching lever 5 is manually moved from the state shown in FIG. 1 to the right against the biasing force of the spring 6 until it comes into contact with the stopper 7f and is held there. Then, since the dowel 4d of the filter holding member 4 is fitted into the groove 5G of the filter switching lever 5, the filter holding member 4 rotates counterclockwise about the shaft 4a, and the filter 4b moves to the photographing lens 1.
enters the optical path of At this time, when the filter holding member 4 rotates counterclockwise, the elongated hole 4c causes the feeding cam ring 3 to rotate clockwise, and the lens barrel 2 is thereby fed forward by a predetermined amount, resulting in the state shown in FIG. The focal position is changed to the shorter distance side.

This example is photographed. -/Oga F4.5. The diameter of the permissible circle of confusion is φ0.09, and the just focus position is set at 3 m so that the subject distance can be covered from 1.5 m to infinity when the filter is not used, and 2.0 m when the filter is used. Extend the photographing lens 1 so that the distance is just 2 m in focus, and set the subject distance to 1.3 m.
The diameter of the circle of confusion was set to cover 7 m with a diameter of φ0.09. As a result, when the filter is used, compared to when the filter is not used, the focus is better when the subject distance is short, and the background at infinity is also easily blurred, so that good portrait embroidery shadows can be achieved.

FIG. 3 shows another embodiment of the invention.

In order to simplify the explanation, the same parts as in the previous embodiment are given the same reference numerals, and only the different points will be explained.

In this embodiment, the filter 4b1 of the filter support member 4 is made into a convex lens, and the filter itself has optical power.
When using the filter, the object distance of the just bin is moved to the short distance side, and except for the mechanism that links the rotation of the filter support member 4 and the extension of the lens barrel 2, the photographing lens 1 is designed to be extended especially when the filter is used. It is something that should not be done.

The other configurations are the same as those of the previous embodiment.

In this embodiment with the above structure, when using the filter, the photographic lens 1
Since there is no need for a feeding mechanism, the device is simple and can be manufactured without increasing costs.

Effects of the Invention> As explained above, the present invention provides a low-cost camera by moving the focus position N (width possible shadow distance) of the photographing optical system to the side where the subject distance is closer when photographing using a filter. This has the effect of allowing good portrait photography to be performed using a fixed focus camera.

Furthermore, by providing power to the filter, a special mechanism for extending the photographic lens is not required, and it is possible to similarly perform portrait photography with a fixed-focus camera without increasing costs.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a camera with a built-in filter according to an embodiment of the present invention, showing when the filter is not used, FIG. 2 shows when the filter is used, and FIG. 3 is another embodiment of the present invention. FIG. 2 is a schematic plan view of a camera with a built-in filter. DESCRIPTION OF SYMBOLS 1... Photographing lens, 2... Lens barrel, 3... Extension cam ring, 4... Filter support member, 4b... Filter, 4b1... Powerful filter, 5...
Filter switching lever 6...Spring, 7a, 7b, 7C
, 7d. ．． ．． Dowel, 7e. 7f...Stopper 1st Figure 5Fq Rudana sword I#retS:- Figure 2

Claims (1)

[Claims] 1. In a camera that includes a built-in filter that is movable between a first position where it enters the photographing optical path and a second position where it retreats outside the photographic optical path, when the filter is in the first position. and second
A camera with a built-in filter characterized in that a photographing lens or a photographing optical system consisting of a photographing lens and a filter has a different focal position when the camera is in the position shown in FIG. 2. The filter has its own optical power, and when the filter is in the first position, the focal position of the photographing optical system is closer to the short distance side than when it is in the second position. A camera having a built-in filter according to claim 1. 3. The camera with a built-in filter according to claim 1 or 2, wherein the filter is a filter for portrait photography having functions such as center image and soft focus.