JPH04326314A - Remote control system of camera - Google Patents

Abstract

PURPOSE:To select the different range finding methods by a remote control device in accordance with a photographing state in order to adjust the focus even if an object does not exist in a range finding area, and also, in order to adjust the focus to the range finding area even if a remote control operator is in the outside of a photographing view angle. CONSTITUTION:A remote control device 10 transmits signals from a first and a second remote control release parts 11, 12 of a remote control AF mode and a regular remote control mode, from a remote control signal transmitting part 13. Subsequently, in a camera main body 20, a first and a second remote control signals are received and each of them is discriminated by a remote control signal discriminating part 22, and based on intensity of a first and a second remote control signals, a distance is measured by an object distance detecting part 24. In a switching part 27, this distance and a distance measured by a range finder part 25 are selected by an instruction of a control part 26, and by using the selected distance output, a lens driving part 29 drives a photographic lens.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera remote control system, and more particularly to a camera remote control system that allows selection of a distance measurement method using a remote control device in a camera having a plurality of distance measurement methods.

0002

2. Description of the Related Art Recently, the number of cameras equipped with an automatic focusing device that includes a remote control (hereinafter abbreviated as remote control) device as a system has been increasing. In these cameras, an infrared remote control signal is transmitted from the remote control device, this signal and the camera receive it, operate the camera's automatic focusing device to focus the photographic lens, and then take a picture. be.

[0003]Referring to FIG. 9, a conventional camera remote control system technique will be described. In the figure, when the person operating the remote control for camera 1 is in front of the camera, that is, at position 2, automatic focusing can be performed without any problem.

0004

However, if the person operating the remote control is not in front of the camera, that is, in the position 3 in FIG. 9, automatic focusing may not be performed correctly. The reason for this will be explained using FIG. 10.

In FIG. 10(a), 4 indicates the angle of view of the finder. 5 is a distance measurement area located at the center of the shooting angle of view. In such a camera, distance measurement cannot be performed if the subject is not in the center. Therefore, if the person operating the remote control is at position 3, it is not possible to properly focus on the person operating the remote control.

[0006] In order to solve this problem, the method shown in Fig. 10 (
As shown in b), there is a method of providing a plurality of distance measurement areas (three in the figure) within the photographing angle of view. If such a method is used, even if the person operating the remote control is not in front of the camera, he or she only needs to cover the distance measurement area 6, 7, or 8, thereby reducing the probability of a problem occurring. However, since a person operating the remote control may enter between the ranging areas, the probability of a problem occurring is not completely zero.

[0007] As a method to solve this problem,
There is a method of determining the strength of the remote control signal received by the camera and then determining the subject distance from that strength. The strength of the remote control signal is inversely proportional to the square of the subject distance.

As described above, the method corresponding to the remote control AF mode in which the object distance is determined based on the intensity of the remote control signal has no problem if the remote control photographer and the object are the same. However, if they do not match, for example when shooting with a remote control from outside the shooting angle of view, or when using a remote control instead of a cable release, the method of determining the subject distance based on the strength of the remote control signal may be inconvenient. . In such cases, it is desirable to use the distance measuring device in the camera body to perform focusing (usually in remote control mode).

The present invention has been made in view of the above-mentioned problems, and it is possible to focus even if there is no subject in the distance measurement area, and it is also possible to focus on the distance measurement area even if the remote control operator is outside the shooting angle of view. The purpose of the present invention is to provide a camera remote control system that allows you to focus on your camera.

0010

[Means for Solving the Problems] That is, the present invention provides a remote control system comprising a camera body and a remote control device for remotely controlling the camera body from the outside, in which the remote control device has first and second remote control release means. and,
A first remote control signal is transmitted to the camera body in response to the operation of the first remote control release means, and a second remote control signal different from the first remote control signal is transmitted to the camera body in response to the operation of the second remote control release means. The camera body is provided with a receiving means for receiving the first and second remote control signals and outputting the received signals, and a receiving means for receiving the first and second remote control signals and transmitting the first and second remote control signals to the camera body. a first distance measuring means for detecting the intensity of the first or second remote control signal received by the receiving means and measuring a subject distance based on this intensity; a second distance measuring means for measuring the subject distance using the camera body alone, regardless of the strength of the first or second remote control signal; It is characterized by comprising a selection means for selecting either the distance output of the first or second distance measurement means, and a photographic lens driving means for driving the photographic lens using the distance output selected by the selection means. do.

[0011]

[Operation] In the camera remote control system of the present invention, the remote control device side has a remote control AF mode that determines the object distance based on the strength of the remote control signal and focuses the photographic lens, and a remote control AF mode that focuses the photographic lens by determining the object distance based on the strength of the remote control signal, and a Two types of remote control release means are provided: a normal remote control mode for focusing the photographic lens according to the output. and,
By appropriately switching between these two modes depending on the shooting situation, correct focusing can be achieved even when the remote control operator and the subject are different.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a camera remote control system of the present invention. This camera remote control system includes a remote control device 10 and a camera body 20 that is remotely controlled from the outside by the remote control device 10. ing.

The remote control device 10 is composed of a first remote control release section 11, a second remote control release section 12, and a remote control signal transmitting section 13. The remote control signal transmitting section 13 outputs a first remote control signal in response to the output signal from the first remote control release section 11. Similarly, the remote control signal transmitting section 13 outputs a second remote control signal having a different signal form from the first remote control signal in response to the output signal from the second remote control release section 12.

On the other hand, the camera body 20 includes a receiving section 21 and
Remote control signal discrimination section 22 and remote control signal strength detection section 2
3, a subject distance detection section 24, a distance measurement section 25, a control section 26, a switching section 27, a lens drive amount determination section 28, and a lens drive section 29. The output signal from the remote control device 10 received by the receiving unit 21 is subjected to discrimination between a remote control signal and a noise signal, and further discrimination between the first remote control signal and the second remote control signal, in a remote control signal discriminating unit 22. conduct. In addition, the remote control signal strength detection section 2
3 inputs the output signal from the receiving section 21 and detects the strength of the signal. This remote control signal strength detection section 23
The output signal is input to the object distance detection section 24, and the distance to the object is detected.

The control unit 26 includes a remote control signal discriminator 2
In response to the output signal from the control section 26, the switching section 27 switches between the subject distance detection section 24 and the ranging section 25. Select and output one of the output signals from the . Then, the lens drive amount determining section 28 selects the switching section 2.
The amount of drive of the photographing lens is determined in response to the output signal of 7, and the amount of drive of the lens drive unit 29 is determined according to the determined amount of drive.
is what drives the photographic lens.

FIGS. 2(a) and 2(b) show external views of the camera remote control system of the present invention. In FIG. 2(a), the entire surface of the camera body 20 has a window 20 for receiving a remote control signal from the remote control device 10.
1 is provided.

Furthermore, the remote control switch 10 shown in FIG. 2(b)
are provided with remote control release switches 101 and 102. These remote control release switches 101
The remote control release operated by and 102 includes 2
There are two modes. One method according to the present invention calculates the distance to the subject based on the strength of the remote control signal received by the camera body 20, calculates the amount of drive of the photographic lens from that distance, and drives the photographic lens to take the photograph. This is the mode to do this. This mode is called remote control AF mode. When performing remote control photography using remote control AF, a remote control AF release switch 101 is used.

Another mode is a mode in which the AF sensor on the camera side focuses the photographing lens. This mode is used when a photographer performs remote control shooting from outside the shooting angle of view, or when using the remote control device 10 instead of a cable release. This mode is called the normal remote control mode. When performing remote control photography in this normal remote control mode, the normal remote control release switch 102 is used. Note that the remote control device 10 is further provided with a window 103 for transmitting a remote control signal.

FIG. 3 is a schematic circuit diagram of the remote control device 10. As shown in FIG. A remote control AF release switch 101 and a normal remote control release switch 102 are connected to the remote control CPU 104 . The remote control CPU 104 also includes a resistor 105 and a transistor 106.
An infrared-emitting LED 108 for transmitting a remote control signal is connected to a drive circuit consisting of the following, via a current-limiting resistor 107. In addition, 109 is a lens for condensing light, and LE
It has a function of condensing the light from D108 and outputting it at a fixed angle.

Next, referring to FIG. 4, the timing of the optical signal output from the remote control signal will be explained. Figure 4
(a) is an optical signal in remote control AF mode. Further, FIG. 4(b) shows an optical signal in the normal remote control mode. Both modes output two groups of burst waves, but the cycles of the burst waves are different in both modes. The period of these burst waves is Tx1 in remote control AF mode, and Tx2 in normal AF mode.

FIG. 5 is a schematic circuit diagram of the camera body 20. As shown in FIG. In the figure, 202 is the remote control device 10.
This is a lens for condensing the optical signals sent from the source. The remote control signal focused by this lens 202 is photoelectrically converted by a silicon diode (SPD) 203 and then output to a remote control signal processing circuit 204.

[0023] This remote control signal processing circuit 204
The output signal of D203 is processed and the remote control signal REM and signals UEL and LEL representing the amplitude of the remote control signal are output to the camera CPU 205. This camera CPU
205 is for performing sequence control on the camera body 20 side. The camera CPU 205 also includes an AF sensor 206 for detecting the defocus amount and defocus direction of the photographing lens, and a photographing lens control circuit 207 for controlling the driving of the photographing lens in order to focus the photographic lens. are combined. In addition, 208 is a first release switch (1RSW) that is turned on with the first stroke of the release button, 209 is a second release switch (2RSW) that is turned on with the second stroke of the release button, and 210 is a remote control shooting switch. This is a remote control mode changeover switch (RMSW) that switches between a mode in which remote control photography is permitted and a mode in which remote control photography is prohibited.

Next, the internal circuitry of remote control signal processing circuit 204 will be explained with reference to FIGS. 6 and 7(A) to 7(H). The light receiving element 203 is an S having sensitivity only in the infrared light region.
The PD receives a remote control signal from a remote control device 10 as shown in FIG. 7(A). In addition, the preamplifier 211 has high-pass filter (HPF) characteristics, and cuts the stationary light component and commercial frequency light source noise contained in the photoelectron of the light receiving element 203, and filters the signal light as shown in FIG. 7(B). Converts only current to voltage.

Next stage band pass filter (BPF) 21
2 is the same center frequency f0 as the carrier frequency f0 of the first and second burst waves transmitted from the remote control device 10.
It has a voltage gain peak at 0 and is used to cut noise at frequencies lower and higher than that. The output of the BPF 212 shown in FIG. 7(C) is the output of the detection circuit 2
13 and detected as shown in FIG. 7(D). Thereafter, the detected signal is input to the integrating circuit 214, and the carrier frequency f0 component is removed (see FIG. 7(E)). The output of the integrating circuit 214 is input to the waveform shaping circuit 215 and waveform shaped (see FIG. 7(F)).
After that, it is input to the camera CPU 205.

In this way, the first and second burst waves from the remote control device 10 as shown in FIG. 7(A) are
The signal is converted into a pulse signal as shown in FIG. 7(F). Then, the camera CPU 205 reads the time Tx from the falling edge E1 of this signal pulse to the falling edge E2 of the next signal pulse. The camera CPU 205 measures this time Tx and determines whether the remote control AF mode is the normal remote control mode.

Further, the envelope of the output signal of the BPF 212 is detected by envelope detection circuits 216 and 217. The envelope detection circuit 216 is a circuit for detecting an upper envelope signal (see FIG. 7(G)) with respect to the output signal of the BPF 212 shown in FIG. 7(C), and includes a diode 218, a capacitor 219, It is composed of a resistor 220. Here, the time constants of the resistor 220 and the capacitor 219 are set to be sufficiently large for the carrier signal synchronization T0, but sufficiently small for the burst wave interval Tx.

Similarly, the envelope detection circuit 217
This is a circuit for detecting the lower envelope signal (see FIG. 7(H)) with respect to the output signal of the BPF 212,
It is composed of a diode 221, a capacitor 222, and a resistor 223.

These envelope detection circuits 21
The outputs of 6 and 217 are sent to buffer circuits 224 and 225.
via the respective envelope signals UEL and LE
L is output to the camera CPU 205. This camera CPU
205 inputs these UEL and LEL signals and sends them to A.
/D conversion and find the amplitude of the remote control signal from the difference in level. This amplitude is between the remote control device 10 and the camera body 2.
It is inversely proportional to the square of the distance difference between 0 and 0. Therefore, the camera CPU 205 can determine the distance to the subject from these signals.

Next, referring to the flowchart of FIG.
The operation of this embodiment will be explained. This flowchart is a flowchart showing a subroutine in remote control mode. The camera has two shooting modes: a remote control mode that allows remote control shooting, and a non-remote control mode that prohibits remote control shooting. These two modes are
Switch each time RMSW is turned on.

First, in step S1, RMSW is monitored. Here, if the RMSW is on, the process moves to step S2, the remote control mode is canceled, and the process returns. Further, in step S1, if the RMSW is not turned on, the process proceeds to step S3 to perform side lighting. This side illumination is performed by a photometric circuit (not shown), and the photometric value is input to the camera CPU 205. Also, camera CP
U205 inputs film sensitivity information from a film sensitivity input device (not shown), performs apex calculation according to a predetermined program from these photometric values and film sensitivity information, and determines the aperture value and shutter speed to be controlled;
Display is performed on a display circuit (not shown).

Next, in step S4, the REM signal is monitored. If REM is at a low level ("L"), the process proceeds to step S5, where a timer for measuring the period of the REM signal is reset and started. Then, in step S6, the REM signal is monitored and the REM signal is
If the signal becomes high level (“H”), the process moves to step S7. In this step S7, the REM signal is monitored again, and when the REM signal becomes "L", the count value of the timer is entered into the Tx register in step S8.

Next, in step S9, the value of the Tx register is compared with the constant TA in terms of magnitude. Here, if Tx<TA, it is the remote control AF mode, so the process proceeds to step S10, and a timer for a certain period of time is activated. Here, as shown in FIG. 7, the REM signal (
(see figure (F))), the second falling point T1,
UEL signal (see figure (G)) and LEL signal (see figure (G))
Since there is a slight time difference between the peak time T2 (see H), a timer corresponding to this time difference is operated.

Next, in steps S11 and S12, A/D conversion of UEL and LEL is performed, respectively. Then, in step S13, a distance calculation is performed. This distance calculation is performed based on the difference between the A/D converted values of the UEL and LEL. As a result, the distance to the subject can be determined. Next, in step S14, a defocus amount is calculated. Once the distance to the subject is determined, the absolute position of the photographic lens to be moved can be determined. therefore,
The defocus amount of the photographic lens can be determined from the current position of the photographic lens. Thus, in step S15, the photographing lens is driven based on the defocus amount obtained in step S14.

On the other hand, in step S9, TX≧
If it is TA, the normal remote control mode is in effect, and the process advances to step S16 to perform AF. AF operates the AF sensor 206 in the camera body 20, inputs pixel data from the AF sensor 206 to the camera CPU 205, and performs AF calculation. Then, the amount of defocus and the direction of defocus of the photographic lens are detected. Next, in step S17, the photographing lens is driven based on the defocus information obtained in step S16. Thereafter, photometry is performed in step S18.

[0036] Also, in step S4 above, REM
If = "H", the remote control signal is not being input, so the process advances to the next step S19 and the 1RSW is monitored. If the 1RSW is not on, step S1
Return to On the other hand, if the 1RSW is in the on state, the process advances to step S20 and AF is performed. Next, step S2
After the lens is driven in step S1, photometry is performed in step S22.

[0037] Then, in step S23, 2RSW
If the 2RSW is in the on state, a release sequence is performed in step S24, and then the process returns to step S1. Also, in step S23, 2R
If the SW is not on, the process moves to step S25 and 1RSW is monitored. In this step S25, if the 1RSW is on, the process returns to step S23, and if the 1RSW is not on, the process returns to step S1.

In this way, by making it possible to switch between the remote control AF mode and the normal remote control mode using the remote control device, correct focusing can be achieved even when the remote control photographer and the subject are different.

[0039]

As described above, according to the present invention, it is possible to focus even if there is no subject in the distance measurement area, and also to focus on the distance measurement area even if the remote control operator is outside the shooting angle of view. We can provide a camera remote control system that can

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a camera remote control system according to the present invention.

FIGS. 2(a) and 2(b) are external views of the camera body and the remote control device.

FIG. 3 is a schematic circuit configuration diagram within the remote control device of FIG. 1;

FIG. 4 shows optical signals output from the remote control device; (a) is a timing chart of the optical signal in remote control AF mode, and (b) is a timing chart of the optical signal in normal remote control mode. .

FIG. 5 is a schematic circuit configuration diagram of the camera body of FIG. 1;

FIG. 6 is a circuit configuration diagram of the remote control signal processing circuit of FIG. 5;

7A to 7H are signal waveform diagrams at locations indicated by A to H in the remote control signal processing circuit of FIG. 6, respectively; FIG.

FIG. 8 is a flowchart illustrating the operation of the camera in remote control mode.

FIG. 9 is an explanatory diagram of a conventional camera remote control system technology.

FIG. 10(a) is a diagram showing the viewfinder shooting angle of view when there is one distance measurement area, and (b) is a diagram showing the viewfinder angle of view when there is one distance measurement area.
FIG. 3 is a diagram showing the photographing angle of view of the finder in the case of three objects.

[Explanation of symbols]

10... Remote control device, 11... First remote control release section,
12... Second remote control release section, 13... Remote control signal transmitting section, 20... Camera body, 21... Receiving section, 22... Remote control signal discrimination section, 23... Remote control signal strength detection section, 24...
Subject distance detection unit, 25... Distance measurement unit, 26... Control unit, 27
...Switching unit, 28...Lens drive amount determining unit, 29...Lens drive unit, 104...Remote control CPU, 204...Remote control signal processing circuit, 205...Camera CPU, 206...AF sensor, 207...Photographing lens control circuit.

Claims (1)

[Claims] 1. A remote control system comprising a camera body and a remote control device for remotely controlling the camera body from the outside, wherein the remote control device includes first and second remote control release means; Transmitting means for transmitting a first remote control signal to the camera body in response to an operation, and transmitting a second remote control signal different from the first remote control signal to the camera body in response to the operation of the second remote control release means. The camera body is provided with a receiving means for receiving the first and second remote control signals and outputting the received signals, and receiving means for inputting the receiving means and discriminating the first and second remote control signals into the first remote control signal and the second remote control signal. a discrimination means; a first distance measuring means for detecting the intensity of the first or second remote control signal received by the receiving means and measuring a subject distance based on this intensity; and the first or second remote control signal. a second distance measuring means that measures the distance to the subject using the camera body alone, regardless of the intensity of the second distance measuring means;
a selection means for selecting one of the distance outputs of the first or second distance measuring means based on the first or second remote control signal discriminated by the discrimination means; 1. A camera remote control system comprising: a photographic lens driving means for driving a photographic lens using a photographic lens.