JPH04251234A - Display device of camera - Google Patents

Abstract

PURPOSE:To provide the display device for cameras constituted to allow easy judgment of whether the subject in a nonfocusing region among plural focus detection regions is included within the depth of field or not. CONSTITUTION:A computing means 104 computes the information associated with the depth of field in accordance with the information on the subject distance for the focusing regions and the set aperture value of a photographic lens. A deciding means 105 decides whether the subject existing in the non- focusing region off the focusing regions among the plural regions exists within the above-mentioned depth of field or not by comparing the information associated with the computed depth of field and the information on the detection of respective focuses. A display control means 106 controls a display means 103 so as to display the focusing region, the non-focusing region decided to be within the depth of field and the non-focusing region decided to be off the depth of field in respectively different forms.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device used in a camera that focuses a photographic lens on a subject in one of a plurality of regions within a photographic screen.

0002

[Prior Art] Conventionally, cameras have been known that perform focus detection in a plurality of focus detection areas within a photographic screen and focus a photographing lens on a subject in one of the areas (focus areas). (For example, JP-A-1-120520). In addition, some cameras of this type display a focus area where the photographing lens is focused among the plurality of focus detection areas on the photographing screen in the viewfinder (for example, Japanese Patent Laid-Open No. 1-277225 Publication No.).

0003

[Problem to be Solved by the Invention] However, since the latter camera described above only displays the in-focus area, the subject in other areas (out-of-focus area) is within the depth of field. It is not possible to determine whether it is included or not. For this reason, in the past, if you wanted to focus on a subject that was out of focus, you would narrow down the aperture based on intuition or experience, and in this case you would end up narrowing down the aperture more than necessary and unnecessarily changing the shutter speed. There was a real risk that it would be delayed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a camera display device that makes it easy to determine whether or not a subject in an out-of-focus area among a plurality of focus detection areas is included within the depth of field. It is in.

[0005]

[Means for Solving the Problems] To explain with reference to FIG. 1 which is a diagram corresponding to claims, the present invention provides a focus detection means 10 capable of outputting focus detection information for a plurality of areas within a photographing screen.
1, and a focusing means 10 that selects a predetermined focus area from a plurality of areas and focuses the photographing lens on a subject in the focus area based on focus detection information for the focus area.
The present invention is applied to a display device used in a camera equipped with 2. Display means 103 capable of displaying each of the plurality of regions in at least three display modes, subject distance information for the in-focus region, and information related to the depth of field based on the set aperture value of the photographic lens. The calculation means 104 that calculates information compares the calculated depth of field related information with each output focus detection information, and determines whether the subject is located in an out-of-focus area other than the in-focus area among the plurality of areas. Determination means 10 for determining whether the photograph is located within the depth of field.
5, and a display means for displaying the in-focus area, the out-of-focus area determined to be within the depth of field, and the out-of-focus area determined to be outside the depth of field, respectively, in different manners. 103, thereby solving the above problem.

[0006]

[Operation] The determining means 105 compares the depth of field related information calculated by the calculating means 104 and each focus detection information outputted by the focus detecting means 101, and compares the depth of field related information calculated by the calculating means 104 with each focus detection information outputted by the focus detecting means 101. It is determined whether the subject located in the in-focus area is located within the depth of field. The display control means 106 controls the display means 103 to display the focus area and
An out-of-focus area determined to be within the depth of field and an out-of-focus area determined to be outside the depth of field are displayed in different manners.

[0007]

[Embodiment] An embodiment of the present invention will be explained with reference to FIGS. 2 to 11. FIG. 2 is a diagram showing the overall configuration of a camera display device according to the present invention. 10 is a camera body, and 20 is a photographic lens barrel attached to this camera body 10. As shown in the figure, the main mirror (half mirror) 1 inside the camera body 10
1 is in the down position (non-photographing state), part of the subject light that has passed through the photographing lens 21 in the lens barrel 20 is reflected upward by the main mirror 11, and the reflected light is reflected by the focusing plate 12 and the pentameter. The light passes through the prism 15 in order and is observed through the eyepiece 16.

On the other hand, a part of the subject light that has passed through the photographing lens 21 is transmitted through the main mirror 11 and then passes through the sub-mirror 1.
The light is reflected downward at 1a and guided to the AF sensor module 18 disposed at the bottom of the camera body 10. The AF sensor module 18 has a photoelectric conversion element that receives input object light and converts it photoelectrically, and its photoelectric conversion output (image
signal) is input to the focus detection circuit 33. The focus detection circuit 33 performs a predetermined focus detection calculation based on the input image signal, and calculates the defocus amount (
(including the defocus direction) and inputs it to the control circuit 32. This defocus amount corresponds to focus detection information.

In this embodiment, three sets of the above photoelectric conversion elements are provided, and three focus detection areas 51A,
Focus detection of objects located at 51B and 51C is possible. Therefore, the focus detection circuit 33
Three defocus amounts corresponding to A to 51C are calculated.

As shown in FIG. 4, the focusing plate 12 has a Fresnel lens 12a formed on its lower surface (light entrance surface) and a light diffusing surface 12b formed on its upper surface (light exit surface). Three display sections 12A, 12B, and 12C each consisting of a large number of prism aggregates are formed on the exit surface. These display sections 12A to 12C are for displaying the three focus detection areas 51A, 51B, and 51C.

Reference numeral 34 denotes a light projecting optical element provided in front of the focusing plate 12, and as shown in FIG. , 35c are provided. Each of these LED packages 35a to 35c includes
Three light emitting diodes each emitting red, blue, and yellow light (
LEDs (hereinafter referred to as LEDs) are housed and held, and each LED is controlled to light up by a light emission control circuit 36. For example, as shown in FIG.
Here, the light is further reflected and enters the light incident surface of the focusing plate 12. The incident light is transmitted through the Fresnel lens 12a
and enters the pentaprism 15 via the display section 12A.

As shown in FIG. 6, out of the LED light passing through the focusing plate 12, the light passing through the display section 12A (indicated by L1) is converted into light from the pentaprism 15 by a plurality of prism aggregates. Light that is refracted toward the reflective surface 15a and passes through areas other than the display section 12A (indicated by L2) is diffused by the light diffusing surface 12b and is not guided to the light reflective surface 15a. Therefore, when the LED in the package 35a emits light, only the image of the display section 12A is observed through the eyepiece 16 together with the subject image. The image on this display section 12A is
As shown by 52A in FIG. 5, it is displayed so as to surround the focus detection area 51A. Similarly, when the LEDs of the LED packages 35b and 35c are turned on, images on the display sections 12B and 12C are displayed as shown by 52B and 52C. In this embodiment, as described above, each package 3
Since three light emitting diodes 5a to 35c are provided to emit red, blue, and yellow light, display in these three colors is possible.

Next, the control procedure by the control circuit 32 will be explained with reference to flowcharts shown in FIGS. 7 to 10. When the release button (not shown) is pressed halfway, this program is started, and first, in steps S1 to S3 of FIG. 7, the focus detection area 5 is
Focus detection is performed for each of 1A to 51C (FIG. 3). That is, the focus detection circuit 33 is activated to detect the area 5 described above.
The photographing lens 21 is output from the three outputs (image signals) of the AF sensor module 18 corresponding to 1A to 51C, respectively.
The defocus amount of each is calculated.

[0014] Next, in step S4, it is determined which area of the subject the photographic lens 21 should be focused on (for example, the closest subject should be focused on). Here, the area determined above corresponds to the in-focus area, and the other areas correspond to the out-of-focus area. Next, in step S5, a lens driving amount is calculated based on the one corresponding to the determined focusing area among the three calculated defocusing amounts, and in step S6, a lens driving amount is calculated according to the lens driving amount. The signal is output to a lens drive circuit (not shown) to drive the photographing lens 21 to the in-focus position. That is, the photographing lens 21 is brought into focus on the subject in the focus area.

In step S7, the defocus amounts df1 and df2 of the two above-mentioned out-of-focus areas are respectively calculated when the defocus amount of the in-focus area is set to zero, and step S7 is performed.
In step 8, the depth of focus (depth of field related information) is calculated from the set aperture value and subject distance. Here, the above aperture value is the one set by the photographer (when set in aperture priority mode or manual mode), or the subject brightness and film sensitivity detected by a photometer (not shown) when the release button is pressed halfway. This is the value calculated from (when set to program mode). The object distance is a value detected by a distance encoder (not shown) after the lens is driven.

Next, the process proceeds to step S9 in FIG. 8, where it is determined whether the defocus amount df1 of one of the out-of-focus areas calculated in step S7 is included within the calculated depth of focus. If step S9 is affirmed, step S
Proceed to step 10 yellow display processing, and if negative, step S1
Proceed to step 1, red display processing. Here, the fact that the defocus amount df1 of this out-of-focus area is included within the depth of focus means that the subject located in that area is located within the depth of field with respect to the focused state of the photographic lens 21, Not being included within the depth of focus indicates that the subject located in that area is located outside the depth of field.

Details of the yellow display process in step S10 are shown in the subroutine of FIG. In FIG. 9, steps S51 and S52 are performed so that the area (here, the area corresponding to the defocus amount df1) is 51 shown in FIG.
This is a process of determining any one of A to 51C. If it is the area 51A, step S51 is affirmed and the process proceeds to step S53; if the area 51B, step S52 is affirmative and the process proceeds to step S54; if it is the area 51C, step S52 is negative and the process proceeds to step S55.

In steps S53 to S55, the yellow LED among the LEDs corresponding to the areas 51A to 51C, respectively, is turned on via the light emission control circuit 36. The light of this LED (yellow light) is transmitted to the display section (12A to 12) as described above.
C corresponding to the relevant area), and the image on the display section is observed through the eyepiece lens 16 via the pentaprism 15. In other words, the area in the photographic screen 50 is covered with a yellow frame. after that,
The process returns to the process shown in FIG.

FIG. 10 is a subroutine showing details of the red display process in step S11. In FIG. 10,
In steps S61 and S62, it is determined which area the relevant area is in the same manner as described above. Based on the determination result, in any of steps S63 to S65, a red LED corresponding to the area is made to emit light for display. In other words, that area is covered with a red frame. Thereafter, the process returns to the process shown in FIG.

In steps S12 to S14 in FIG. 8, the same processing as in steps S9 to S11 described above is performed for the out-of-focus area where the defocus amount is df2. Then step S1
In steps 5 to S19, it is determined which area is the in-focus area, and the area is displayed using a blue LED in the same manner as described above.

The above is the procedure of display processing, and then when the release button is operated, a photograph is taken. According to the above procedure, the in-focus area among multiple focus detection areas is displayed in blue, the out-of-focus area within the depth of field is displayed in yellow, and the out-of-focus area outside the depth of field is displayed in yellow. Displayed in red. In this way, each of the three types of areas is displayed in a different display color, which not only makes it easier to determine the in-focus area, but also allows you to check whether the subject in the out-of-focus area is within the depth of field. It is also possible to easily determine whether or not.

FIG. 11 shows an example in which the center area 51B is the in-focus area and the subjects in the two left and right out-of-focus areas 51A and 51C are outside the depth of field.
is displayed in blue, and the other areas 51A and 51C are displayed in red. Therefore, the photographer
If you want to focus on subjects A and 51C,
As shown in FIG. 12, the aperture may be narrowed down until the areas 51A and 51C are displayed in yellow. According to this, it is possible to focus on the out-of-focus areas 51A and 51C without unnecessarily narrowing down the aperture. In particular, in this embodiment, the above-mentioned display is displayed on the photographing screen in the finder, so that the above-mentioned judgment can be made while looking through the finder, which is convenient.

The flowchart in FIG. 13 is an example of a procedure for changing the display state by narrowing down the aperture. This example is applied to a camera with a half-press timer.
It shows the processing after the processing of FIGS. 7 to 10 described above is completed. The half-press timer is a half-press timer that maintains the power for a predetermined period of time even after the release button has been released.
It is possible to display 12C.

When the release button is released after the display is performed according to the steps shown in FIGS. 7 to 10, the program shown in FIG. 13 is started. In step S91, timing for the half-press timer is started, and then, when it is determined in step S92 that the aperture value has been changed, in step S93, the depth of focus is calculated based on the changed aperture value and the subject distance at that time. The process is performed again, and in step S94, the processes of steps S9 to S19 in FIG. 8 are performed, and the process returns to step S92. If step S92 is negative, it is determined in step S95 whether or not there is a half-press operation, and if it is determined that a half-press operation has been performed, timekeeping is ended and the process proceeds to step S1 in FIG. If it is determined that there is no half-press operation, it is determined in step S96 whether or not the time is up. If negative, the process returns to step S92, and if affirmative, the time measurement is ended and the process is ended.

According to the above procedure shown in FIG. 13, the aperture is narrowed down during the half-press timer, and as a result, for example,
When the subject in the out-of-focus areas 51A and 51C enters the depth of field, the display changes to the state shown in Fig. 12, so by confirming this display change before performing the release operation,
It is possible to focus on the out-of-focus areas 51A and 51C without unnecessary narrowing down.

In the configuration of the above embodiment, the AF sensor module 18 and the focus detection circuit 33 function as the focus detection means 101, and the control circuit 32 functions as the focusing means 102,
The calculating means 104 and the determining means 105 are connected to the display section 12A.
12C constitutes the display means 103, and the control circuit 32, the light emission control circuit 32, and each LED constitute the display control means 106, respectively.

[0027] In the above, the three areas, the in-focus area, the out-of-focus area within the depth of field, and the out-of-focus area outside the depth of field, are displayed in different colors, but for example, if the same It may be possible to distinguish by color by lighting or blinking the display. For example, if the in-focus area is lit, the out-of-focus area within the depth of field is blinking, and the out-of-focus area outside the depth of field is blinking (or off) with a different duty from the above. good. Also,
For example, the display shape may be changed to distinguish between circles, triangles, and squares. Furthermore, the structure of the display section is not limited to the above-mentioned one; for example, a self-luminous display section such as an electroluminescent device may be used, or a non-luminous display section such as an electrochromic device may be used. Good too. Furthermore, the display is not limited to the viewfinder, but may be displayed on a liquid crystal display on the surface of the camera body in correspondence with each focus detection area.

[0028] Furthermore, although the focus detection method is described above using the so-called TTL phase difference detection method, the present invention is not limited to this, and may be an active distance measuring method that detects the subject distance by triangulation distance measurement, for example. In this case, the above object distance corresponds to focus detection information, and the depth of field is calculated using the object distance in the in-focus area, and the calculated depth of field and the object distance in the out-of-focus distance are calculated. It may be determined whether or not the depth of field is within the depth of field by comparison.

[0029]

[Effects of the Invention] According to the present invention, the in-focus area, the out-of-focus area determined to be within the depth of field, and the out-of-focus area determined to be outside the depth of field are respectively Since the display is displayed in a different manner, you can easily judge whether the subject in the out-of-focus area is included in the depth of field or not, and you can avoid narrowing down the aperture more than necessary, unlike in the past, which was based on intuition and experience. This allows the subject in the out-of-focus area to be included in the depth of field, and prevents the shutter speed from being unnecessarily slowed down.

[Brief explanation of the drawing]

FIG. 1 is a complaint correspondence diagram.

FIG. 2 is a configuration diagram of a display device of a camera according to an embodiment of the present invention.

FIG. 3 is a diagram showing a focus detection area in a photographic screen and its display state.

FIG. 4 is a perspective view showing a focus plate and a display section.

FIG. 5 is a diagram showing the configuration of a finder optical system.

FIG. 6 is a diagram illustrating an optical path of LED light passing through a focusing plate.

FIG. 7 is a main flowchart showing the procedure of display processing.

FIG. 8 is a flowchart following FIG. 7;

FIG. 9 is a flowchart showing a subroutine.

FIG. 10 is a flowchart showing a subroutine.

FIG. 11 is a diagram showing a display example.

FIG. 12 is a diagram showing another display example.

FIG. 13 is a flowchart according to another embodiment.

[Explanation of symbols]

12 Focus board 12A-12C Display section 15 Pentaprism 16 Eyepiece lens 18 AF sensor module 21 Photography lens 32 Control circuit 33 Focus detection circuit 34 Light projecting optical element 35a-35c LED package 36 Light emission control circuit 50 Shooting screen 51A-51C Focus detection area 101 Focus detection means 102 Focusing means 103 Display means 104 Arithmetic means 105 Judgment means 106 Display control means

Claims (3)

[Claims] 1. Focus detection means capable of outputting focus detection information for a plurality of areas within a photographic screen; and a focus detection means for selecting a predetermined focus area from the plurality of areas and based on the focus detection information for the focus area. In a display device used in a camera, the display device includes a focusing means for focusing a photographing lens on a subject in the focusing area, wherein the plurality of areas are
display means each capable of displaying in at least three display modes; a calculation means for calculating information related to depth of field based on object distance information with respect to the in-focus area and a set aperture value of the photographing lens; Comparing the calculated depth of field related information with each of the output focus detection information, it is determined that the subject located in an out-of-focus area other than the in-focus area among the plurality of areas is within the depth of field. determining means for determining whether or not the in-focus area is located within the depth of field; the in-focus area; the out-of-focus area determined to be within the depth of field; and the out-of-focus area determined to be outside the depth of field and display control means for controlling the display means to display the images in different manners. 2. The display device for a camera according to claim 1, wherein the display means displays the display within a finder. 3. The display means is capable of displaying in at least three display colors, and the display control means controls the display means to display each of the three types of areas in different colors. A display device for a camera according to claim 1 or 2.