JPS6219823A - Focusing device - Google Patents

Abstract

PURPOSE:To put an optional partial block in focus selectively by selecting one or >=2 optional partial blocks in a photodetection part where plural couples of photodetecting elements are arrayed and providing selection switches corresponding to respective partial blocks. CONSTITUTION:The photodetection part 2 is formed by arraying plural couples of photodetecting elements 2a and 2b laterally in a line. The output of the photodetection part 2 is supplied to a microcomputer 4 through an A/D converter 3 to perform arithmetic processing and a motor 6 for driving a distance ring is driven through a driving circuit 5 according to the processing result. Further, selection switches S1-S4 are connected to the computer 1. The switches S1-S4 are independent of one another and optional partial blocks are selected in the photodetection part 2 by turning on the switches S1-S4 to input their outputs to the computer 4. Thus, such partial blocks that, for example, the face of a person as an object of focusing is included are selected and the target object of focusing is put in focus.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a focusing device that uses a light receiving section formed by arranging a plurality of pairs of light receiving elements.

(Prior art) Focusing device, especially automatic focusing device (autofocusing device)
Conventionally, active methods using infrared rays or ultrasonic waves, and passive methods using photodiode arrays, CCDs, etc. are known.

The active method measures distance by a so-called triangulation method, which projects infrared rays or the like and detects the infrared rays or the like reflected by the subject to be focused.

On the other hand, the passive method is equipped with a light-receiving section using a CCD or the like in which multiple pairs of light-receiving elements are arranged, and measures distance by detecting the phase difference between the light-receiving signals obtained from the pair of light-receiving elements. The output signal (data) from the camera is processed by a microcomputer or the like, and the results of this processing are used to adjust the focus.

(Problems to be Solved by the Invention) However, both of the above-described conventional focusing devices employing the active method and the passive method have a problem of causing out-of-focus when used.

In other words, in the active method, it is necessary to focus the beam narrowly so that the infrared rays etc. can reach a long distance, so when the subject is far and near, so-called hollowing occurs, and even if you intend to focus on a close subject, The camera may focus on a distant subject, or vice versa.

In addition, in the passive method, A
A control signal corresponding to the direction and amount of movement of the focus ring is generated by performing predetermined processing such as /D conversion processing and arithmetic processing, but when the object to be focused on is small and there are different distances around the object, If an object exists, the above processing result becomes a solution for the intermediate distance between the two, that is, between the in-focus object and the surrounding objects, and a phenomenon occurs in which neither object is in focus. Therefore, depending on the manner of use, out-of-focus may occur.

(Means for solving the problems) The present invention aims to solve the above-mentioned conventional problems.
This is achieved by the following focusing device.

That is, the focusing device 1 (FIG. 1) according to the present invention includes a light receiving section 2 in which a plurality of pairs of light receiving elements 2a and 2b are arranged, processes the output of this light receiving section 2, and uses the processing results. In particular, passive focusing devices that adjust the focus using
Select one or more arbitrary partial blocks AI, A2, A3 from the light receiving section 2, and select a selection switch S corresponding to each partial block A1, A2, A3.
L, S2, S3, and S4 are arranged, and the selection switch S
Any partial block A by L, S2, S3, S4
It is characterized by being able to focus by selecting I, A2, or A3.

(effect) Next, the operation of the present invention will be explained.

The focusing device 1 according to the present invention can arbitrarily select corresponding partial blocks Al, A2, and A3 using selection switches 81 to S4. That is, the partial block AI can be selected by turning on the selection switch S1, and similarly A2 can be selected by 82, A3 by S3, and A 1 + A 2, for example, by S4.

It is now assumed that a subject H shown in FIG. 2 is imaged on the light receiving section 2.

That is, a face H1 of a person at a relatively close distance is imaged on the partial block A1, a house H2 at a medium distance is imaged on A2, and a mountain H3 at a long distance is imaged on A3. In this case, when each partial block is not selected, all the subjects H are imaged on the light receiving section 2, and as described above, there may be cases where none of the subjects H1 to H3 is in focus. Therefore, in such a case,
When it is desired to focus on the face H1 of a person, by turning on the selection switch S1, it is possible to focus only on the partial block A1 corresponding to the face H1.

(Example) Hereinafter, preferred embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a block configuration diagram of a focusing device according to the present invention, and FIG.
3 and 3 are explanatory diagrams of the operation of the present invention.

First, the configuration of a focusing device indicated by reference numeral 1 will be explained.

Reference numeral 2 denotes a light receiving section, which includes an optical sensor section using a CCD, an integrating function section, a shift register section, and the like.

The optical sensor section includes a pair of light receiving elements (unit CCD) 2a and 2b.
It is formed by arranging multiple sets in a straight line in the horizontal direction.

On the output side of the light receiving section 2, there is a circuit A that performs analog-to-digital conversion.
/Connect D converter 3.

A microcomputer 4 is connected to the output side of the A/D converter 3 and performs arithmetic processing on input data.

A distance ring drive motor 6 is connected to the output section of the microcomputer 4 via a drive circuit 5.

Further, selection switches Sl, S2, S3, and S4 are connected to the microcomputer 4 according to the present invention. Each of the selection switches 31 to s4 is independent, and the selection information obtained by turning on the switches 81 to s4 becomes input data to the microcomputer 4.

Next, the functions of the focusing device 1 will be explained.

When an image of a subject is formed on the light receiving section 2, an analog signal for distance measurement is sequentially applied to the output of the light receiving section 2. This analog signal is A/
It is converted into a digital signal for processing by a microcomputer via a D converter 3, and this signal is input to a microcomputer 4 as input data. The microcomputer 4 processes input data, measures distance, and outputs control data for focus adjustment. Then, this control data is supplied to the motor 6 via the drive circuit 5, and the focus ring is extended.
Drive the distance ring to focus.

Note that such a focusing function is publicly known.

On the other hand, input data from the light receiving section 2 is processed as follows using the arithmetic processing function of the microcomputer 4.

First, one or more arbitrary partial blocks are selected from the light receiving section 2. The selection method is as shown in Figure 2.
The light-receiving section 2 may be divided into a plurality of (three in this example) blocks Al, A2, and A3, starting from the end of the light-receiving section 2, or an arbitrary portion A4 of the light-receiving section 2 may be sequentially enlarged as shown in FIG. By doing so, a plurality of blocks (three in this embodiment) may be selected.

The microcomputer 4 can extract and process only arbitrary blocks from each of the blocks A1, A4, and so on. In this case, a desired block can be selected by turning on any corresponding one of the selection switches 81 to S4.

As a result, for example, when the selection switch S1 is turned ON, the corresponding block A1 is selected, and the microcomputer 4 performs arithmetic processing only on the light-receiving elements present in the block A1, which is a part of the light-receiving section 2, while other blocks A2 and A3 are canceled.

Such a selection can be made using predetermined software (control program), or alternatively, the light receiving section 2 may be connected separately using hardware and can be switched using the selection switches 81 to S4.

Note that the selection switches 31 to S4 are arranged, for example, on the outside of a camera (particularly a video camera) so that the photographer can manually operate them.

Next, we will explain how to use it.

Currently, most of the subjects are in the far (medium) distance.
Alternatively, in the case of only a person at a short distance, the selection switches 31 to S4 are not used (but the focus is good. However, as shown in FIG. 2 (or FIG. If the person's RH1) is relatively small and there are subjects H2 and H3 at different distances around the subject, the in-focus point will be at an intermediate position between H1 and H2 (or H3), making it possible to focus accurately. In such a case, if you turn on the selection switch S1 to select the partial block A1 that contains the face H1 of the person who is the focus target, you can immediately focus on the focus target. I can do it.

Although the embodiments have been described in detail above, the present invention is not limited to the illustrated embodiments.

For example, the method for selecting partial blocks is not limited to the example shown, and any method may be used, and the number of blocks may also be selected arbitrarily.

Other details such as configuration, shape, arrangement, quantity, etc. may be arbitrarily changed without departing from the spirit of the present invention.

(Effects of the Invention) As described above, the focusing device according to the present invention selects one or more arbitrary partial blocks from the light-receiving section, and is provided with a selection switch corresponding to each partial block. ,
Since an arbitrary partial block can be selected and focused using the selection switch, the following effects can be obtained.

■It can effectively prevent defects that occur due to the large light-receiving area of passive focusing devices such as those using CCO, that is, out-of-focus caused by usage conditions, and is always accurate regardless of the environment (usage conditions). can be focused on.

■It can be easily configured in terms of circuitry and can be provided at low cost.

It also has excellent expandability, with the ability to operate the camera in both automatic and manual modes.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram of a focusing device according to the present invention, and FIG.
FIG. 3 is an explanatory view of the operation of the present invention. In the drawings, 1... Focusing device, 2... Light receiving section, 2a, 2b... Light receiving element, A1.
A2. A3. A4. A5. A6...partial block, SL, S2. S3. S4 - Selection switch.

Claims (1)

[Claims] 1. In a focusing device that includes a light receiving section in which a plurality of pairs of light receiving elements are arranged, processes the output of the light receiving section, and performs focus adjustment using the processing result, one or more of the light receiving sections are arranged. Selecting two or more arbitrary partial blocks,
1. A focusing device characterized in that a selection switch corresponding to each partial block is provided, and an arbitrary partial block can be selected and focused using the selection switch.