JP2979157B2 - Camera with distance display function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera having a built-in distance measuring circuit, and more particularly to a camera capable of displaying distance information as a result of distance measurement.

[0002]

2. Description of the Related Art For example, in a compact camera having a built-in distance measuring circuit, several devices for informing a camera user of a result of distance measurement have been proposed. A typical example is a guideline in the viewfinder. This is the “flower” and “person” drawn in the viewfinder when ranging is completed.
The pointer moves on a scale symbolizing the image of distance such as "mountain", and the distance is roughly displayed.

[0003]

However, in such a conventional distance display device, since the scale indicating the distance is a vague image, it is roughly called "near", "normal" or "far". There was a problem that only a short distance was known. Also, depending on the country or region, the region where the meter method is used as the unit of distance and the field
In some areas, the law is used. When the distance is to be displayed as a numerical value, if the distance is displayed in correspondence with both units, the display becomes small in a limited space, and there is a problem that it is difficult to see.

[0004] It is an object of the present invention to provide a camera in which the distance obtained as a result of distance measurement can be directly read out by a numerical value, the distance display unit can be used for displaying other information, and the distance unit can be changed. Is to do.

[0005]

The present invention will be described with reference to FIG. 1 which is a diagram corresponding to the claims. The present invention provides a distance measuring circuit 100 for detecting and outputting information relating to the distance to a subject.
And a half-press switch means 120 which is turned on when the release button is half-pressed and activates the distance measuring circuit 100 by this ON signal, and a release switch means 130 which is turned on by a full-press operation of the release button. Applied. A display means 110 having an element for displaying a distance to a subject as a result of distance measurement by the distance measurement circuit 100, and a film counter display using the element, and a half-press switch. When the means 120 is turned on, the distance measurement result output from the distance measuring circuit 100 is converted into distance display data and displayed on the display means 110. When at least the half-press switch means 120 is not turned on, the display is performed. Film display by element
The above-mentioned object is achieved by providing the control means 140 for controlling the change to the counter display. The invention of claim 2 is
The above object is achieved by providing the distance unit selection means 150 for selecting the distance unit of the distance measurement result displayed on the display means 110.

[0006]

When the half-press switch means 120 is turned on, the distance measuring circuit 1 is turned on.
00 operates, the result of the distance measurement is converted into distance display data by the control means 140 and output to the display means 110. Thus, the directly readable distance is numerically displayed on the display unit 110. When the half-press switch means 120 is not turned on, the distance display on the display means 110 is
The display is changed to the film counter display. When the distance unit selection means 150 is operated, the distance on the display means 110 is displayed in the selected unit. This enables a desired unit of distance display.

[0007]

FIG. 2 is an overall block diagram showing an embodiment of the present invention. In FIG. 2, an arithmetic and control circuit 1 composed of a one-chip microcomputer controls the entire camera, and selects a distance unit as a result of distance measurement, a photographing process accompanying a pressing operation of a release button, and a distance measurement. It has a result display processing function.

The arithmetic and control circuit 1 has a main display for displaying the distance measurement result.
Unit changeover switch 2 for selecting a unit of torque (m) and feet (ft), a half-press switch 3 which is turned on by half-pressing a release button (not shown), and a release switch 4 which is turned on by fully pressing a release button (not shown). Are connected to each other, and the other end is connected to the negative electrode of the battery power supply 8. The arithmetic and control circuit 1 includes a nonvolatile memory 5 such as an electrically rewritable E2PROM, an autofocus circuit (hereinafter referred to as an AF circuit) 6 for distance measurement, and a display 7 comprising a liquid crystal or the like. Are connected respectively. In the non-volatile memory 5, it is necessary to hold the distance display data corresponding to each unit of meter and feet, such as tabulated data and selected and set units, even when the power is turned off. Is stored (for example, FIG. 7). The AF circuit 6 executes a distance measuring process according to a command when the arithmetic control circuit 1 captures the ON signal of the half-press switch 3, and converts the distance measurement result into a step value for setting a display distance in the arithmetic control circuit 1. It is used for searching the distance display data table. The display 7
Is provided on a camera body or the like, and displays necessary information such as a distance and the number of photographed films in accordance with an output signal from the arithmetic and control circuit 1. Further, an arithmetic control circuit 1, a nonvolatile memory 5, and an AF circuit 6 are connected to the battery power supply 8.

FIG. 3 shows a specific example of the display unit 7, which is a 7-segment numeric display pattern 81, 82, 83 made up of an LCD, a decimal point 84 made up of an LCD, and "ft" and "ft". m "unit marks 85 and 86. These three numerical display patterns 81, 82, 8
By using 3 and the decimal point 84, 0.00,
0.01 to 9.99, 10, and 11 to 999 can be expressed.

Next, the operation of the embodiment constructed as described above will be described with reference to FIGS. FIG. 4 is a flowchart showing an overall flow of a portion related to a distance measurement result display function of the camera. In FIG. 4, when the power is turned on by turning on a main switch (not shown), a distance measurement result display program starts. As a result, the unit selected before the battery was removed in step S10 is read from the nonvolatile memory 5 and taken into the arithmetic and control circuit 1. In the next step S20, the display 7 displays the number of film shots so far. Then, in the next step S30, it is determined whether or not the changeover switch 2 for selecting meter / feet has been turned on. Here, when it is determined that the switch is off, the process proceeds to step S40, and it is determined whether the half-press switch 3 is turned on. When the changeover switch 2 is turned on, the process shifts to step S50 to execute m / ft selection processing.
Go to 0.

On the other hand, in step S40, the half-press switch 3
When it is confirmed that is turned on, the process proceeds to step S60 to execute the photographing process, and when it is completed, the process proceeds to step S70. If it is determined that the half-press switch 3 is off, the process proceeds to step S70, and it is determined whether the main switch is on. If it is determined to be on, step S
The process returns to step 30 and waits for one of the switches 2 or 3 to be turned on again. When it is determined that the main switch is off, the display processing of the distance measurement result ends.

Next, m / f shown in step S50 of FIG.
The t selection processing procedure will be described in detail with reference to the flowchart shown in FIG. The units m and ft are not switched immediately when the changeover switch 2 is turned on, but are changed only when the changeover switch 2 is kept turned on for 3 seconds. This is to prevent the unit from frequently changing due to an erroneous operation of the changeover switch 2. First, in step S501, a 3-second timer for counting the ON time of the changeover switch 2 is started. Note that the three-second timer is configured in software by a CPU and a RAM (both not shown) constituting the arithmetic control circuit 1.

In the next step S502, it is determined whether or not the changeover switch 2 has been turned on. If the switch 2 has been turned on, the flow shifts to step S503 to determine whether or not the 3-second timer has expired. If it is confirmed that the changeover switch 2 is turned off within three seconds, the unit is not changed, and the process proceeds from step S504 to FIG.
Return to the flowchart of FIG. If the time-up is confirmed in step S503, the process proceeds to step S505, where the current m
Determine the / ft setting. Here, if it is determined to be "ft", the process proceeds to step S506 to set "m", and if it is determined to be "m", the process proceeds to step S506.
The flow shifts to 507, where "ft" is set. Next step S
In step 508, step S506 or step S507
Is displayed on the display 7. Then, in the next step S509, the set unit data is written to the nonvolatile memory 5. Hereinafter, the same loop is repeated until the changeover switch 2 is turned off, and the setting is switched every three seconds. Therefore, if the changeover switch 2 is turned off when a desired unit is selected, the display can be switched between m / ft.

Next, the photographing processing procedure shown in step S60 in FIG. 4 will be described in detail with reference to the flowchart shown in FIG. First, photometric processing is performed in step S601. That is, although the details are omitted, the brightness of the subject is calculated from the amount of light input to the light receiving element, the shutter opening time is determined, and at the same time, it is determined whether the brightness is low, and it is determined whether the strobe light emission is necessary. And the next step S60
In step 2, a distance measurement process is performed. That is, when the half-push switch 3 is turned on, the arithmetic and control circuit 1 which has confirmed the half-press switch 3 sends a distance measurement start signal to the AF circuit 6 to cause the AF circuit 6 to perform a distance measurement operation. When the distance measurement is completed, the result of the distance measurement by the AF circuit 6 is taken into the arithmetic and control circuit 1. The arithmetic control circuit 1 calculates a step value for setting the display distance from the distance measurement result, and this step value is used as a read control signal for the distance display data table.

FIG. 7 shows a part of the relationship between the step value and the distance measurement result and the distance display data. For example, when the distance measurement result is 2.509 m or more and 3.007 m or less, the step value is shown. "5" and 0.99 for 0.943m or more
If the distance is 5 m or less, a step value “16” is output. When the step value "5" is output, "2.74" is displayed in the distance display data of the unit "m", and "9.04" is displayed in the distance display data of the unit "ft". Each is set.

In the next step S603, it is determined whether or not it is determined that strobe light emission is necessary. Here, if the flash emission is not required, the process proceeds to step S604, and if the flash emission is required, the process proceeds to step S617. In step S617, it is determined whether or not charging for strobe light emission has been completed. When it is determined that charging has been completed, the process proceeds to step S604. If it is determined that the charging has not been completed, the flow shifts to step S618 to wait for the half-press switch 3 to be turned off. No shooting is performed at this time.
When it is confirmed that the half-press switch 3 is off, the flow returns to the flow of FIG.

When strobe light emission is not necessary, or when strobe light emission is necessary and charging is completed, photographing is possible, and the distance display described below is executed. First, in step S604, the unit setting of m / ft is confirmed. When the unit is set to "m", the process proceeds to step S605, and when the unit is "ft", the process proceeds to step S60.
Proceed to 7. In step S605, referring to the distance display data table in the nonvolatile memory 5 corresponding to the unit "m", the address is designated by the calculated step value and the corresponding distance display data is read (step S606). . The read distance display data is sent from the arithmetic control circuit 1 to the display 7.
And the distance as a result of the distance measurement is digitally displayed by a meter method (step S609). For example, when the step value is “14”, “1.09” is designated as is clear from FIG. 7, and this numerical value is displayed on the display 7.

Similarly, if "ft" has been set, in step S607, the step value calculated by referring to the distance display data table in the nonvolatile memory 5 corresponding to the unit "ft" is referred to. The corresponding distance display data is read out by designating the address in step S6.
08). Then, by outputting the read data to the display 7, the distance as a result of the distance measurement is digitally displayed in the form of feet (step S609). At this time, assuming that the step value is "14", "3.60" in the data table shown in FIG. 7 is designated, and this is displayed on the display 7 as a numerical value. In the next step S610, it is determined whether or not the release switch 4 is on. If it is determined that the release switch 4 has been turned on by fully pressing the release button, the flow shifts to step S611 to open and close the shutter, and at the same time, in the strobe light emission mode, the strobe light is emitted to photograph the subject. Is made. Thereafter, in step S612, the distance display displayed on the display 7 is cleared, and instead, the number of photographed films is displayed on the display 7, and in step S613, the film is wound. Then, in the next step S614, if it is confirmed that the half-press switch 3 is turned off, the flow returns to the flow of FIG.

If it is determined in step S610 that the release switch 4 is off, step S61 is performed.
The program proceeds to 5 where it is determined whether the half-press switch 3 is off. Here, when the half-press switch 3 is turned on, step S610
And waits until the half-press switch 3 is turned off or the release switch 4 is turned on. If it is determined that the half-push switch 3 is off, the flow advances to step S616 to clear the distance display displayed on the display 7.
Instead, the number of photographed films is displayed.

FIG. 8 shows a display state when the display 7 functions as a film counter, and the displayed numerical value indicates the 24th frame. 9 and FIG.
0 indicates a display state when the display 7 is made to function as a distance display of a distance measurement result in units of meters or feet. According to such a configuration, most of the commonly used distance range can be represented in addition to the film counter display.

In this embodiment, the distance as a result of the distance measurement by the AF circuit 6 when the release button is half-pressed is digitally displayed on the display 7 in the unit of desired meter or feet. be able to. Accordingly, since the distance as a result of the distance measurement can be directly read by a numerical value, it is possible to quantitatively know the distance to the subject at the time of photographing, thereby photographing the subject at a distance desired by the photographer. . Further, since the distance as a result of the distance measurement is displayed on the display device, the distance measurement result can be displayed in an easy-to-understand manner with an appropriate size even in a limited space. Furthermore, when the half-press switch 3 is turned off or the release switch 4 is turned on by full-press, the distance measurement result on the display 7 is cleared, and instead, the number of photographed films is displayed. With this configuration, the display for displaying the distance can be used for the display of the number of sheets. Further, by switching the unit changeover switch 2, the desired distance unit can be selected as the distance measurement result.

The number of steps for the distance measurement result in the present invention is not limited to the number of steps divided as shown in FIG. 7, but the present invention can be applied to a method in which the number of steps is further reduced to improve the display distance accuracy. Further, in the above embodiment, the meter and the feet are described as the unit of the distance display. However, the present invention is not limited to this, and may be applied to, for example, yards, inches, and scales. I can do it. Further, the number of distance unit selections is not limited to the two units described in the above embodiment, and a camera having three or more units can be implemented. Further, the installation place of the display 7 is not limited to the camera main body shown in the above embodiment, but may be provided in the viewfinder.

In the above embodiment, the arithmetic control circuit 1 controls the control means 140, the unit changeover switch 2 controls the distance unit selection means 150, the half-press switch 3 controls the half-press switch means 120, and the release switch 4 controls the release switch. The means 130, the AF circuit 6 and the display 7 constitute the distance measuring circuit 100 and the display means 110, respectively.

[0024]

As described above, according to the present invention, when the release button is half-pressed, the distance as a result of the distance measurement is numerically displayed on the display unit, so that the distance measurement result can be directly read and the half of the release button can be read. When the push is released, the distance display can be changed to the film counter display and the number of films can be displayed, so that the installation space of the display element is not so much required. Further, according to the present invention, by enabling selection of a distance unit, distance display can be performed in a desired unit such as meters or feet.

[Brief description of the drawings]

FIG. 1 is a view corresponding to a claim of a camera according to the present invention.

FIG. 2 is an overall configuration diagram showing one embodiment of the present invention.

FIG. 3 is a display segment pattern diagram showing a specific example of a display.

FIG. 4 is a flowchart illustrating an entire flow of a distance measurement result display function of the camera in the present embodiment.

FIG. 5 is a flowchart illustrating m / ft selection processing according to the present embodiment.

FIG. 6 is a flowchart illustrating a photographing process according to the present embodiment.

FIG. 7 is a diagram showing tables of distance measurement results, the number of steps, and distance display data.

FIG. 8 is an explanatory diagram showing a display example of the number of films.

FIG. 9 is an explanatory diagram showing an example of distance display in meter units.

FIG. 10 is an explanatory diagram showing an example of distance display in a unit of a foot;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Operation control circuit 2 Unit switch 3 Half-press switch 4 Release switch 5 Non-volatile memory 6 AF circuit 7 Display 100 Distance measuring circuit 110 Display means 120 Half-press switch means 130 Release switch means 140 Control means 150 Distance unit selection means

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-61-53625 (JP, A) JP-A-54-24018 (JP, A) JP-A-53-97827 (JP, A) (58) Field (Int.Cl. ⁶ , DB name) G03B 17/18-17/20 G02B 7/28-7/40 G03B 3/00-3/12

Claims (2)

(57) [Claims] 1. A distance measuring circuit for detecting and outputting information related to a distance to a subject, and a half-press switch means which is turned on when a release button is half-pressed, and which activates the distance measuring circuit in response to the ON signal. And a release switch means that is turned on by a full-press operation of the release button. A camera having a distance display function, comprising: an element for displaying a distance to a subject, which is a distance measurement result of the distance measurement circuit. line the film counter display in
A display means as earthenware pots, the during on operation of the half-stroke switch means, a distance measurement result the distance measuring circuit outputs distance indication de - and displays on the display means is converted into data, press at least the half A camera with a distance display function, comprising: control means for changing a display by the display element to a film counter display when the switch means is not turned on. 2. A camera with a distance display function according to claim 1, further comprising a distance unit selecting means for selecting a distance unit of a distance measurement result displayed on said display means.