JPH08110553A - Camera - Google Patents

Abstract

PURPOSE: To prevent the occurrence of a trouble such as bite in a focusing lens driving mechanism by inhibiting a focusing lens operation including a reset operation when a rear cover is opened. CONSTITUTION: The camera is provided with a photointerrupter 1 for detecting the position of the focusing lens, a photoreflector 3 for detecting a feeding quantity and a photoelectric conversion element signal processing circuit 5 for processing signals from the photointerrupter 1 and the photoreflector 3. And before performing the focusing operation and the reset operation of the focusing lens, whether or not the rear cover is opened is judged by a rear cover switch 7, and in the case the rear cover is opened, the focusing lens operation is not executed by a microcomputer 6. Thus, the reset operation of the focusing lens is not executed in the state where the rear cover is opened, so that such the troubles are prevented that out-of-focusing occurs at the following photographing and the photographing is made in an error state because of the inaccuracy in the reset operation due to the influence of external light made incident on the photoreflector 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera capable of detecting a film feeding amount and a focusing lens position by using a photoelectric conversion element.

[0002]

2. Description of the Related Art In recent lens shutter cameras, in order to reduce the size of the camera, the film feed amount is often detected by using a photoelectric conversion element such as a photo reflector instead of a sprocket.

Some lens shutter cameras having an autofocus function use a stepping motor as a focusing lens driving actuator. The stepping motor is suitable for the autofocus function because it is easy to control the driving amount in steps. When the focusing lens is controlled by using the stepping motor, some absolute position detecting means is required, and a photoelectric conversion element such as a photo interrupter may be used for detecting the position of the focusing lens of this lens shutter camera. .

FIG. 12 shows an example in which a photo interrupter is used to detect the position of such a focusing lens. In FIG. 12, reference numeral 43 is a stepping motor, which rotates the shaft 42 by a predetermined amount by applying a step-like energization waveform. The shaft 42 is threaded, and when it is rotated forward, the lens support member 44 is driven in the feeding direction indicated by the arrow, and when it is rotated backward, the lens support member 44 is driven in the feeding direction opposite to the arrow.

The focusing lens 45 and the light blocking plate 41 are fixed to the lens supporting member 44, and when the lens supporting member 44 is driven by the rotation of the shaft 42, both the focusing lens 45 and the light blocking plate 41 move. 1 is
It is a photo interrupter in which a light projecting element and a photoelectric conversion element are integrated and which outputs a dark signal when a slit portion (not shown) is blocked and a bright signal when it is not blocked. The photo interrupter 1 is fixed to a stationary member (not shown), and the light shielding plate 41 passes through the slit thereof. In FIG. 12, the lens support member 44 and the lens 4
The output of the photo interrupter 1 is inverted from a dark signal to a bright signal or vice versa at a portion 5 indicated by a solid line.

In FIG. 12, the stepping motor 4
It is configured such that the direction of the arrow in the drawing away from 3 is the feeding direction.

FIG. 12A shows the state of the output signal of the photo interrupter 1 when the lens support member 44 moves along the shaft 42. The lens support member 44 is on the horizontal axis.
In the direction of the axis 42, and the vertical axis represents the output signal.

In FIG. 12, when the lens support member 44 is located on the stepping motor 43 side, the dark signal (the L level portion on the left side of FIG. 12A) is blocked because the light blocking plate 41 blocks the slit portion of the photo interrupter 1. Is output.
Then, the lens support member 44 is extended, and the lens support member 44 and the focusing lens 45 are beyond the position where the output of the photo interrupter 1 shown by the solid line is inverted, and the lens support member 44 and the focusing lens 45 of FIG. Is extended to the position indicated by the broken line, the light shielding plate 41 does not block the slit portion of the photo interrupter 1, so that a bright signal (H-level portion on the right side of FIG. 12A) is output.

The output of the photo interrupter 1 shown in FIG. 12 (a) changes gently as shown in the figure due to the influence of reflection and diffraction. This signal is binarized by passing through a signal detection circuit that uses a comparator, but the position of the focusing lens 45 can be controlled by setting the position at which this photo interrupter signal output is inverted as the reference position (absolute position). Becomes

The positioning operation of the focusing lens 45 (hereinafter referred to as the reset operation) drives the stepping motor while monitoring the photo interrupter signal,
When the signal is inverted, the stepping motor is driven to the standby position of the focusing lens 45 with reference to the position.

In actual shooting, if the reset operation is performed before shooting, the time required for the reset operation becomes the release time lag. Therefore, the reset operation is performed after shooting or when it is detected that the release button has been released, and when the release button is pressed, the reset operation is not performed and the necessary steps are taken to the in-focus position based on the standby position. Focusing operation is performed by driving several stepping motors.

FIG. 13 is a circuit diagram showing an example of a signal detection circuit of the photo interrupter 1 which is the photoelectric conversion element.

In FIG. 13, reference numeral 2 denotes a constant current circuit which is turned on / off by the microcomputer 6 and which drives the light projecting element 1a of the lens position detecting photointerrupter 1 with a constant current. Reference numeral 5 denotes a light receiving phototransistor 1b of the photointerrupter 1. When the space (slit) between the light projecting elements 1a is shielded by the light shielding plate 41, a signal of D1 = 0 is output as "photointerrupter dark", and the light shielding plate 41 does not block the slit and light is transmitted. Is a photo interrupter signal detection circuit that outputs a signal of D1 = 1 as "photo interrupter clear". As the circuit configuration of the photo interrupter signal detection circuit 5, the detection current Iin by the phototransistor 1b is converted into a voltage signal Vi by the resistor R1.
The reference voltage Vc, which is converted to n and the digital signal output from the microcomputer 6 is analog-converted by the D / A converter 32, is input to the comparator with hysteresis 31 and D1 is output.

By changing the reference voltage Vc, D
The displacement of the focusing lens 45 in which 1 is inverted changes. This makes it possible to adjust the reference position of the focusing lens 45.

Next, an example in which a photo reflector (reflection type photo interrupter) is used for detecting the film feed amount will be described.

FIG. 14 is a rear view of the essential parts of a film feeding section equipped with a photoreflector for detecting the film feeding amount.
The back lid is not shown here.

In FIG. 14, 21 is a film, 22 is a cartridge, 23 is a winding spool for winding the film 21, 24 is an aperture portion for exposing the film 21, and 25 is a perforation. Reference numeral 3 denotes a photoreflector which is a reflection type photoelectric conversion element for detecting the film feed amount, and is attached to a stationary portion (not shown) such that the light projecting / receiving surface is parallel to the surface of the film 21.

In the above structure, when the perforation 25 reaches the light projecting surface during film feeding, the projecting light passes through the perforation 25 and is absorbed by the back cover surface made of a material which is difficult to reflect the light. Since the phototransistor is off, the output of the photoreflector 3 becomes a dark signal. Further, when the film portion between the perforations 25 reaches the light projecting surface, the projected light is reflected by the film and the phototransistor is turned on.
The output of the photo reflector 3 becomes a bright signal.

FIGS. 15 (a) and 15 (b) illustrate the case of detection as the dark signal and the case of detection as the bright signal. This figure is a view of the periphery of the photo reflector 3 in FIG. 14 as seen from above in the figure, and FIG.
26 is a back cover made of a material (not shown in FIG. 14) that hardly reflects light.

Here, as shown in FIG. 15A, when the perforation 25 comes to the light projecting surface and the phototransistor, which is originally a light receiving element, is turned off, that is, even when the photointerrupter signal is a dark signal, the back cover 26 is removed. be opened,
That is, when the film storage portion is opened, the phototransistor receives external light and outputs a bright signal.
This is illustrated in FIG. 15 (c). As a result, the phototransistor cannot perform the original perforation detection associated with film feeding. Therefore, in the feeding control with the back cover 26 opened (such control is performed in the adjustment stage, etc.), the photo-reflector signal is ignored and the pseudo perforation signal is used, or a timer is used. It is controlled by the second control.

By the way, when a photoelectric conversion element such as a photo interrupter is used for signal detection as described above, by using an IC in which the signal detection circuit 5 and the microcomputer 6 are integrated, the signal line to the D / A converter 32 is used. IC
Even if the internal terminal is used and the external terminal of the IC is not used for the D / A converter, two terminals are required for the light emitting element control of the photo interrupter and the phototransistor output signal input. That is, when a plurality of signals are similarly processed by the photoelectric conversion element, the number of terminals required is twice the number of signals to be processed. However, in a device such as a lens shutter camera, which is required to be compact, there is a limitation on the size of the IC, and a terminal is required for other switches and the like. Sometimes it is required to reduce even one.

In the lens shutter camera, the photoelectric conversion element may also be used for shutter control. It is already known to use a signal terminal of a photo reflector for feeding and a signal terminal of a photo interrupter for shutters in order to omit the terminals. By doing so, it becomes possible to use three terminals instead of requiring four terminals when not used in common. However, as described above, when the back lid is open, external light is incident on the photoreflector for feeding, so when the signal terminal is also used, not only the feed control but also the shutter control when the back lid is open. Becomes impossible.

As a means for solving this problem, Japanese Unexamined Patent Publication No.
304536 has been proposed. JP-A-2-30453
In No. 6, when the open state of the back lid is detected, the signal from the shutter photo interrupter is not used, and the shutter control is controlled by a pseudo signal from a timer or the like to solve the above problem.

[0024]

In order to reduce the number of IC terminals, the signal terminals of the photoelectric conversion element are also used, which is different from the above-described feeding photo reflector 3 and focusing lens position detecting photo interrupter 1. Can also be considered. In this case as well, what used to require 4 terminals can be replaced with 3 terminals. Further, when the photoelectric conversion element is also used for shutter control, if this is also used, what is necessary for six terminals will be four terminals.

However, when the focusing lens position detecting photo interrupter and the feeding photo reflector signal terminal are used in common, the following problems occur.

That is, when the back cover is open, external light is incident on the photoreflector for feeding. Therefore, when the back cover is open, the signal level input to the signal terminal is also used when the back cover is open. Fluctuates or sticks to the level of the bright signal, and the inversion position of the signal from the focusing lens position detection photointerrupter 1 is displaced or cannot be detected. When the focusing lens is reset in this state, the reference position of the focusing lens becomes inaccurate, or the lens supporting member 44 and the focusing lens 45 move to the limit of the movable range of the stepping motor without detecting signal inversion. Therefore, in an extreme case, there is a possibility that biting will occur at the limit portion and the subsequent focusing lens 45 cannot be driven, and the focusing operation will be impossible.

When the signal terminal for the shutter is also used, as in Japanese Patent Laid-Open No. 2-304536, since the film is not loaded in the state where the back cover is opened, the shutter control may be a pseudo control. However, since the resetting operation of the focusing lens is intended to detect the absolute position for the next photographing, it does not make sense to perform the pseudo control.

Further, since focus adjustment and the like are performed in a factory with the back cover open, means for solving the above problems and for enabling focus adjustment in the process is required.

Further, in recent years, the downsizing of cameras has been promoted, and an increasing number of cameras reduce the size of the camera when the lens barrel is housed by retracting the lens barrel when the camera is not used. Further, due to the miniaturization, for example, in the case of front lens focusing, there is a camera that is configured such that when the focusing lens is extended, it pops out to the front side of the front surface of the lens barrel. In such a camera, if the lens barrel is stored with the focusing lens extended, the lens barrier may not close due to the protruding focusing lens, and the protruding focusing lens may be easily impacted. turn into. Therefore, while taking measures against the above problems,
There is a need for a means that does not hinder the barrier closing operation, does not give an impact to the focusing lens, and does not affect the housing of the lens barrel.

Further, while taking measures against the above problems, it is necessary to provide a means for preventing out-of-focus from the first sheet of the loaded film when actually loading the film and taking a picture.

[Object of the Invention] An object of the present invention is to provide a camera which solves the above-mentioned problems. The object of the present invention will be described below for each claim.

According to a first aspect of the present invention, there is provided "a first photoelectric conversion element for detecting a feeding state of a film, and a first photoelectric conversion element connected in parallel with the first photoelectric conversion element for detecting a focusing lens position. A second photoelectric conversion element, signal detection means for inputting output signals of the first and second photoelectric conversion elements with a parallel connection point of the first and second photoelectric conversion elements as an input section, and a film storage section And a film storage unit opening / closing detection unit for detecting the opening / closing state of the focusing lens, the focusing lens for prohibiting driving of the focusing lens when the opening state of the film storage unit is detected by the film storage unit opening / closing detection unit. It is an object of the present invention to provide a "camera characterized by being provided with control means".

According to a second aspect of the invention, in the camera having the structure of the first aspect, there is provided a mode setting means for selectively setting the normal operation mode and the adjustment operation mode, and the adjustment operation mode is performed by the mode setting means. Is set, the focusing lens control means permits the driving of the focusing lens even if the film storage portion opening / closing detection means detects that the film storage portion is open. The purpose is to do.

According to a third aspect of the invention, in the camera having the structure of the first aspect, there is provided a barrier for protecting the taking lens, and when the barrier changes from the open state to the closed state, the film storage section opening / closing detecting means. The focusing lens control means moves the focusing lens to the storage position by permitting driving of the focusing lens even if the open state of the film storage section is detected by the camera. And

According to a fourth aspect of the present invention, "In the camera having the structure according to the first aspect, the camera has an automatic film loading (film automatic setting) means, and the focusing is performed when the film loading by the automatic loading means is completed. It is an object of the present invention to provide a "camera characterized in that the lens control means performs an initial positioning operation (reset operation) of the focusing lens".

[0036]

In order to solve the above-mentioned problems, the invention according to claim 1 provides "a first photoelectric conversion element for detecting a feeding state of a film, and a first photoelectric conversion element. A second photoelectric conversion element connected in parallel for detecting a focusing lens position, and the first and second photoelectric conversion elements with the parallel connection point of the first and second photoelectric conversion elements as an input section. In the camera provided with a signal detecting means to which the output signal of (1) is inputted and a film storing portion opening / closing detecting means for detecting the opened / closed state of the film storing portion, the open state of the film storing portion is detected by the film storing portion open / close detecting means. And a focusing lens control means for prohibiting driving of the focusing lens when detected.

According to the present invention, the reset operation of the focusing lens fails due to the influence of the external light entering the camera in the state where the film storage portion is opened (back cover is opened), and the driving mechanism of the lens is strong at the moving end. It is possible to prevent accidents such as biting due to being pressed.

In order to solve the above-mentioned problems, the invention of claim 2 states that "the camera having the structure of claim 1 has a mode setting means for selectively setting a normal operation mode and an adjustment operation mode. When the adjusting operation mode is set by the setting means, the focusing lens control means may permit the driving of the focusing lens even if the film storage portion opening / closing detection means detects that the film storage portion is in the open state. "Featured camera".

According to the present invention, when the film is shipped, the normal photographing mode is set, so that the driving of the focusing lens is prohibited even when the film storage portion (back cover) is opened. There is no bite, and the focusing lens can be driven by setting the adjustment operation mode in the manufacturing process, so the film storage part (back cover) is opened and the focusing lens is reset. Therefore, the focus adjustment work can be easily performed.

In order to solve the above-mentioned problems, the invention of claim 3 is that "a camera having the structure of claim 1 has a barrier for protecting the taking lens, and when the barrier changes from an open state to a closed state. A camera characterized in that the focusing lens control means moves the focusing lens to the storage position by permitting driving of the focusing lens even when the film storage portion opening / closing detecting means detects the film storage portion open state. " I will provide a.

According to the present invention, the barrier closing operation when the use of the camera is finished can be performed without any trouble, and
The camera will not be in a non-use state with the focusing lens protruding. Therefore, the focusing lens is not likely to be impacted.

In order to solve the above-mentioned problems, the invention of claim 4 states: "In the camera having the structure of claim 1, there is an automatic film loading (film automatic setting) means, and the automatic loading means loads the film. Is completed, the focusing lens control means performs an initial positioning operation (reset operation) of the focusing lens.

According to the present invention, it is possible to take a photograph without blurring from the first photographing of the first film after loading a new film. That is, according to the present invention, even if the absolute position of the focusing lens is incorrect as a result of the reset operation of the focusing lens not being performed in the opened state of the film storage portion (back cover) before the film loading, Since the focusing lens reset operation is performed when the loading is completed, a focused photograph can be taken from the time of taking the first first image after the film is loaded.

[0044]

【Example】

(First Embodiment) A concrete embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a drawing which best represents the features of the present invention. The same components as those described in the conventional example are given the same numbers.

Reference numeral 1 denotes a photo interrupter for detecting the position of the focusing lens. As described in the conventional example with reference to FIG. 12, a light shielding plate 41 that moves in conjunction with the focusing lens 45 causes the slit of the photo interrupter 1 to move. It outputs a dark signal when it is blocked and a bright signal when it is not blocked.

Reference numeral 2 denotes a constant current circuit which is turned on / off by the microcomputer 6 and drives the light projecting element of the lens position detecting photo interrupter 1 with a constant current.

Reference numeral 3 is a photoreflector for feeding amount detection, which outputs a dark signal when the perforation of the film comes to the light projecting surface, as described with reference to FIG. 14 in the conventional example. Also, when the film portion between the perforations reaches the projection surface, a bright signal is output.

Reference numeral 4 denotes a constant current circuit which is turned on / off by the microcomputer 6 and drives the light projecting element of the feed amount detecting photo reflector 3 with a constant current.

Reference numeral 5 is a photoelectric conversion element signal processing circuit for processing signals from the lens position detecting photo interrupter 1 and the feed amount detecting photo reflector 3. The output signals of the lens position detecting photo interrupter 1 and the feed amount detecting photo reflector 3 are connected in parallel to a photoelectric conversion element signal processing circuit 5. That is, both output signal terminals are shared.

The configuration of the photoelectric conversion element signal output circuit is the same as that described in the conventional example with reference to FIG. If both the outputs of the photoelectric conversion elements are dark signals, the output D1 = 0 from the photoelectric conversion element signal processing circuit 5
If either of them is a bright signal, D1 = 1. The comparator level in the photoelectric conversion element signal processing circuit 5 is set by the microcomputer 6 by the D / A signal line.

Reference numeral 6 denotes a microcomputer serving as a control means for controlling the operation of the camera body (not shown) such as photometry, distance measurement, release, feeding, and the like, which has a CPU as a core and peripheral functions such as a switch interface and a serial interface. It is configured as a built-in one-chip microcomputer.

Reference numeral 7 denotes a back lid switch which is interlocked with the back lid, which is turned off when the back lid is closed and is turned on when the back lid is open.

Next, the operation of the stepping motor 43 of this embodiment will be described with reference to FIG. In FIG.
The same parts as those described in FIG. 12 in the conventional example are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 2, (a) shows the position of the focusing lens 45 at which the output of the focusing position detecting photointerrupter 1 is inverted.

(B) shows the standby position of the focusing lens 45 after the reset operation. The reason why the standby position (b) is shifted from the signal inversion position (a) is that the signal inversion position is a position where it is unstable whether the output signal of the photo interrupter 1 becomes bright or dark. The standby position is a position at which the output of the photo interrupter 1 is surely output after the predetermined number of steps are extended from the inversion position.

During the focusing operation, the focusing operation is performed by extending or retracting a predetermined number of steps with reference to the standby position.

FIG. 12C is the same as FIG. 12A and shows the state of the output signal of the photo interrupter 1 when the lens support member 44 moves in the direction of the axis 42. The horizontal axis represents the displacement of the lens support member 44 in the direction of the axis 42, and the vertical axis represents the output signal.

(D) shows a state in which the output signal of the photo interrupter 1 is a binarized signal D1 processed by the photoelectric conversion element signal processing circuit 5.

Next, the initial positioning operation (reset operation) of the focusing lens 45 in this embodiment will be described with reference to FIGS.

FIG. 3 is a diagram for explaining the operation of the focusing lens 45 at the time of the reset operation of this embodiment.

In the photoelectric conversion element signal processing circuit 5 of this embodiment, in order to prevent malfunction due to noise, a conventional example shown in FIG.
As described above, a comparator with hysteresis is used as the comparator. Therefore, the microcomputer 6 is used when the signal output of the photo interrupter 1 changes from light to dark and when it changes from dark to light.
Even if the same reference voltage is set, the comparison level changes, and the signal inversion position shifts. In order to prevent this shift, in order to detect the position of the focusing lens 45, the signal inversion position at the time of the change from dark to bright is always used as a reference.

Therefore, the movement of the focusing lens 45 in the reset operation differs depending on whether the output of the photo interrupter 1 at the time of starting the reset operation is dark or bright.

FIG. 3A shows the case where the output of the photo interrupter 1 starts the reset operation by the dark signal, and the arrow in the figure shows the operation of the focusing lens 45.

When the reset operation is started by the dark signal,
The stepping motor 43 is driven step by step in the feeding direction (rightward direction in the figure) until the output of the photo interrupter 1 is inverted. When reaching the reversal position of the photo interrupter output shown by the dotted line in the figure and detecting the reversal of the signal, it is further driven in the feeding direction by a predetermined amount from that point and reaches the standby position of the focusing lens 45 shown by the broken line in the figure. At that point, the reset operation ends.

FIG. 3B shows the operation of the focusing lens 45 when the output of the photo interrupter 1 starts a reset operation with a bright signal. As in the case of FIG. 3A, the arrow in the figure shows the focusing lens 45. It shows the operation.

When the reset operation is started by the bright signal,
Until the output of the photo interrupter 1 is inverted, the stepping motor 43 is driven step by step in the take-in direction (left direction in the figure). When the inversion position of the photointerrupter output shown by the dotted line in the figure is reached and the inversion of the signal is detected (strictly speaking, the signal inversion position is caused by the comparator with hysteresis in the photoelectric conversion element signal processing circuit 5 as described above. Is slightly deviated from the inversion position in dark → bright), and from that point on, the photo interrupter 1 is further driven in the retraction direction by a predetermined amount until the output of the photo interrupter 1 becomes a completely dark signal. Then, this time, the stepping motor 43 is driven step by step in the feeding direction in order to detect the reversal from dark to bright. When the inversion of the signal is detected again, the signal is further driven in the feeding direction by a predetermined amount, and the reset operation is ended when the standby position of the focusing lens 45 shown by the broken line in the figure is reached.

FIG. 4 is a flow chart for explaining the reset operation in more detail.

First, when the reset operation of the focusing lens 45 is started, it is checked in step S101 whether or not the output of the photo interrupter 1 (hereinafter, PI) is a dark signal. In the case of a dark signal, that is, in the case described in FIG. 3A, the process proceeds to step S102. When the output of PI is a bright signal, that is, when it is described in FIG.
Proceed to 107.

In S102, the stepping motor 43 is driven one step in the feeding direction. Next, in S103, it is checked whether the output of PI is inverted to a bright signal. If it is reversed, the process proceeds to S106, and the focusing lens 45 is driven by a predetermined amount in the extending direction to the standby position, and the reset operation of the focusing lens is completed.

If the PI signal is not clearly inverted in S103, the process proceeds to step S104, and it is determined whether or not the limit on the feeding side is reached. If the limit is not reached, the process returns to S102, and the steps S102 to S104 are repeated until the PI signal is inverted or the limit is reached.

Whether or not the limit has been reached can be detected by, for example, a micro switch attached to the axial limit position of the stepping motor 43,
Alternatively, a step number larger than the axial drive limit step number of the stepping motor 43 is set as the limit step number,
It can also be determined by comparing the number of repetitions of S102 to S104 with the number of limit steps.

If the PI output is not inverted before the limit is reached, it is considered that an abnormality such as disconnection of the light projecting element or the light receiving element of the photo interrupter 1 or a stepping out or twisting of the stepping motor 43 has occurred. S10
In step 5, known error processing such as displaying a warning of occurrence of an abnormality and prohibiting further operation is performed, and the reset operation is completed.

Next, the case where the PI output is a bright signal in S101 will be described. In this case, as described above, S
Proceed to 107.

In S107, the stepping motor 43 is driven one step in the retraction direction. Next, in S108, it is checked whether the output of PI is inverted to a dark signal. When the PI signal is not implicitly inverted, the process proceeds to step S109, and it is determined whether or not the limit on the folding side is reached. When the limit is not reached, the process returns to S107, and the steps S107 to S109 are repeated until the PI signal is inverted or the limit is reached. Whether or not the limit has been reached is determined in the same manner as in the case of S104.

If the limit is reached, S1
Since it is considered that some abnormality has occurred as in the case of 04, the process proceeds to step S110, error processing is performed, and the reset operation ends.

When the PI signal is inverted in S108, the process proceeds to S111, and the PI output is further renormalized by a predetermined amount so that the PI output is surely a dark signal. And S10
The process proceeds to step 2, and as described above, in step S102 to step S106, the PI signal is detected to be inverted from dark to bright, and the focusing lens 45 is operated to be positioned at the expected position, thereby ending the reset operation.

Next, the operation during the release sequence of this embodiment will be described with reference to the flowchart of FIG.

The release switch is pressed halfway (hereinafter,
This sequence starts when the state where the release switch is pressed halfway is called the state where SW1 is on and the state where the release switch is released is the state where SW1 is turned off).

When the release sequence is started, the process first proceeds to S201 and a known distance measuring operation is performed. Then S
Proceeding to 202, a known photometric operation is performed.

Next, in S203, the state of the back cover switch 7 is checked to determine whether the back cover is open or closed.

When the back cover is closed, the process proceeds to S204,
Based on the distance measurement result in S201, the stepping motor 4 is moved until the focusing lens 45 reaches the in-focus position.
Drive 3 Then, the process proceeds to S205.

If it is determined in S203 that the back cover is open, S204 is skipped and the process proceeds to S205.

In S205, it is checked whether SW1 is turned off. If not turned off, the process proceeds to S206.

If SW1 is off, the process proceeds to S211, and the state of the back cover switch 7 is checked to determine whether the back cover is open or closed.

If the back lid is closed, proceed to S212,
The reset operation of the focusing lens 45 is performed to complete the release sequence. When the back cover is open, the reset operation may be impossible due to the incident of external light on the feeding amount detecting photo reflector 3,
The reset operation is prohibited and S212 is bypassed to end the release sequence.

If SW1 is not turned off in S205, the process proceeds to S206, and it is checked whether or not the release switch is in a fully depressed state (SW2 is turned on). If SW2 is not turned on, the process returns to S205, and the loop of S205 to S206 is repeated while the SW1 on state continues.

If the SW2 is turned on in S206, the process proceeds to S207, in which known shutter control is performed according to the photometric result in S202. Then, the process proceeds to S208.

In S208, the state of the back cover switch 7 is checked to determine whether the back cover is open or closed.

When the back cover is closed, the process proceeds to S209,
The reset operation of the focusing lens 45 is performed to complete the release sequence. When the back cover is open, the reset operation may be impossible due to the incident of external light on the feed amount detecting photoreflector 3,
The reset operation is prohibited and S209 is bypassed to S21.
Proceed to 0 to feed one frame of film and complete the release sequence.

As described above, in this embodiment, immediately before step S204 for performing the focusing operation and steps S209 and S212 for resetting the focusing lens, it is determined whether or not the back lid is opened, and the back lid is opened. Focusing lens 4 when open
Since the operation of No. 5 is not performed, the reset operation of the focusing lens 45 is not performed in the back cover open state, and the reset operation becomes inaccurate due to the influence of the external light incident on the photoreflector 3 for feeding. Does not cause an out-of-focus state, or the inversion of the photo interrupter signal cannot be detected and the error state does not occur.

In this embodiment, the focusing lens 45 is used.
The reset operation is performed after the release is completed or when SW1 is off. The focusing operation itself does not use the photo interrupter 1 because it does not involve the reset operation, and the focusing operation itself is abnormal due to external light even when the back cover is open. Does not happen. However, if the focusing operation is allowed in the back lid open state, the reset operation is not performed. Therefore, for example, in the case of an optical system including front lens focus, when SW1 is turned on in the back lid open state, the focusing lens is operated by the focusing operation. It is easy to happen that the state is continued even if the SW1 is turned off while the front lens is being fed. In the state where the front lens is extended, the front lens is likely to be impacted. Therefore, in order to avoid such a state, in the present embodiment, the focusing operation is also prohibited when the back cover is open. Has been done.

Also in this embodiment, after the SW1 is turned on with the back lid closed and the focusing operation is performed,
By opening the back cover, the reset operation after turning off SW1 is prohibited, and it is possible to create a state in which the focusing lens 45 is still extended, but this can be done by operating one switch and another operation. Since this is a complex action to perform, it can be considered that such an action is rarely performed unintentionally as compared with the case where the focusing action when the back lid is opened is not prohibited.

(Second Embodiment) In the first embodiment, all the operations of the focusing lens 45 when the back cover is open are prohibited, but the focus adjustment in the process is performed with the back cover open. Therefore, at the time of adjustment, it is necessary to take measures such as blocking the external light from entering the feeding photoreflector 3 and to enable the operation of the focusing lens 45 even when the back cover is open. The second embodiment is an embodiment that takes this problem into consideration.

FIG. 6 is a diagram showing the configuration of the second embodiment. In FIG. 6, the same components as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted.

The structural difference between the first embodiment and the second embodiment is that the EEPROM 8 is added to the second embodiment.

Reference numeral 8 denotes an EEPROM which is a writable non-volatile memory used for writing adjustment data and the like in the manufacturing process and storing information of the film counter during the operation of the camera. Serial clock / SCK from computer 6, serial output SO from microcomputer 6 to EEPROM 8 direction,
The EEPROM 8 is connected to the microcomputer 6 by a serial interface including a serial input SI in the direction of the microcomputer 6. / EPE is a chip select signal for selecting the EEPROM 8 as the partner of serial communication. Further, although these terminals are normally covered, terminals are also provided at locations that can be connected from the outside, and information stored directly in the EEPROM 8 without the intervention of the microcomputer 6 by an external adjusting tool. You can read and rewrite.

A bit for discriminating between the normal operation mode and the adjustment operation mode is prepared in the EEPROM 8, and as described above, the setting of this bit can be performed by the adjustment tool.

Next, the operation of this embodiment will be described with reference to FIG.

FIG. 7 is a flow chart for explaining the operation of the release sequence of the second embodiment of the present invention.

With respect to the release sequence of the first embodiment described with reference to FIG. 5, necessary information is read from the EEPROM 8 during the release sequence including a bit for discriminating the normal operation mode or the adjustment operation mode. Step S301, and a step of inhibiting the operation of the focusing lens 45 depending on whether or not the back lid is opened when the adjustment operation mode is set by the bit for discriminating the normal operation mode or the adjustment operation mode read from the EEPROM 8. S305, S311, S
Step S30 for bypassing each of the 315
4, S310 and S314 are added.

The other steps correspond to the steps of the first embodiment. Steps S302 and S30 of this embodiment
3 corresponds to S201 and S202 of the first embodiment,
Steps S305, S306, S307, S of this embodiment
308 and S309 are S20 of the first embodiment, respectively.
3, S204, S205, S206, and S207, steps S311, S312, and S313 of the present embodiment correspond to S208, S209, and S210 of the first embodiment, respectively.
Steps S315 and S316 of this embodiment correspond to S211 and S212 of the first embodiment, respectively.

Since the corresponding steps perform the same operation, the description of the operation of each corresponding step will be omitted.

In this embodiment, when the bit for operation setting of the EEPROM 8 is set to the normal operation mode, the same operation as that of the first embodiment is performed, so that the operation of the focusing lens 45 with the back cover opened. Therefore, the operation of the focusing lens 45 is not hindered by the external light entering the feeding photo reflector 3.

In addition, the bi for setting the operation of the EEPROM 8 is set.
When t is set to the operation mode for adjustment, the operation of the focusing lens 45 is permitted regardless of the open / closed state of the back lid, so that focus adjustment in the process can be performed.

The mode setting means for the normal operation mode and the adjustment operation mode in this embodiment is not limited to the EEPROM. For example, another writable nonvolatile memory such as a flash memory may be used.

(Third Embodiment) In the first embodiment, the focusing lens 45 is not operated when the back cover is in the open state and in the normal operation mode.

Therefore, in the case where the lens barrel is retracted when the camera is not in use and the camera has an optical system composed of front lens focus, the combined operation of opening the back cover while pressing SW1. When the lens is turned on, the focusing lens 45 may remain extended, and may come out to the front surface rather than the front surface of the lens barrel.

In such a case, as described in the section "Problems to be solved by the invention", the lens barrier does not close due to the protruding focusing lens, and the protruding focusing lens is easily subject to impact. .

The third embodiment of the present invention is an embodiment considering the above points. FIG. 8 is a diagram showing a barrier open / close state of the camera of the third embodiment of the present invention.

FIG. 8A is a front view of the camera of this embodiment, showing the barrier open state. Reference numeral 9 is a slide-type barrier which is linked to the main switch of the camera. Reference numeral 10 is a lens barrel.

FIG. 8B shows the barrier closed state of the camera of this embodiment.

When the barrier 9 is slid in the closing direction from the open state of FIG. 8A, the main switch is turned off, and the lens barrel is retracted and retracted. Barrier 9 is lens barrel 10
Until the lens barrel 10 is completely retracted, the movement in the closing direction is limited by the known locking mechanism so that the lens barrel 10 does not collide with.

When the lens barrel 10 is completely retracted, the lock mechanism is released and the barrier 9 can be completely closed as shown in FIG. 8B.

The focusing lens 45 is retracted to a lens storage position which is a position further retracted from the lens standby position so as not to collide with the barrier 9 when the barrier is closed. The driving to the storage position is basically the same as the focusing operation and only drives the focusing lens 45 for a predetermined number of steps, and the output signal of the photo interrupter 1 is not used. Therefore, it can be executed regardless of the open / closed state of the back lid.

Next, the operation of this embodiment will be described in more detail with reference to the flowcharts of FIGS. 9 and 10.

FIG. 9 is a flow chart for explaining the operation of the present embodiment when the barrier is opened.

When the barrier 9 is changed from the closed state to the completely opened state, the main switch is turned on and the barrier opening process is started.

First, step S401 is executed, and the lens barrel 10 in the collapsed state is driven to a position (a wide end in the present embodiment) where photographing is possible and the amount of movement from the collapsed position is the minimum.

Next, in S402, the state of the back cover switch 7 is checked to determine whether the back cover is open or closed.

When the back cover is closed, the process proceeds to S403,
By performing the reset operation of the focusing lens 45, the focusing lens 45 which has been in the storage position until then is set to the standby position. Then, the process proceeds to S404, and when the main switch is turned on, necessary display lighting is performed, and the barrier opening process ends.

Next, the operation when the barrier is closed will be described.

FIG. 10 is a flow chart for explaining the operation of this embodiment when the barrier is closed.

When the barrier 9 is slid from the open state shown in FIG. 8A and moves in the closing direction, the main switch is turned off and the barrier closing process is started.

First, in step S501, the focusing lens 45 is retracted to the lens storage position. As described above, this operation only drives the focusing lens for the predetermined number of steps and can be executed regardless of the state of the back lid. Moreover, the back cover state is not checked at this time.

Next, in S502, the lens barrel 10 is driven to the retracted position.

Next, in S503, the display turn-off operation performed when the main switch is turned off is performed, and the barrier closing process is ended.

In this embodiment, when the barrier is closed, the focusing lens 45 is retracted to the storage position regardless of the open / closed state of the back lid. Therefore, even when the optical system is configured by the front lens focus, the focusing lens 45 is not used. There is no possibility that the barrier 9 remains protruding from the front surface of the lens barrel 10 and the barrier 9 hits the focusing lens 45 or the barrier 9 cannot be closed.

When the barrier is opened, the open / closed state of the back lid is checked after driving the lens barrel, and the reset operation is performed only when the back lid is closed. It never happens.

In the first to third embodiments, the camera in which the film can be loaded and unloaded by opening and closing the back cover has been described, but the present invention is not limited to this. Needless to say, the present invention can be similarly applied to a camera or the like that can open and close the camera bottom instead of the back cover to load and unload a film.

(Fourth Embodiment) In the first to third embodiments, the reset operation of the focusing lens 45 is not performed when the back cover is in the open state and in the normal operation mode. Therefore, in the case of the front lens focus optical system, if the focusing lens 45 is pushed in the back cover open state and deviates from the standby position, after the first image is taken after the film is loaded,
Alternatively, since the reset operation is not performed until after SW1 is turned off, the shooting is performed by pressing the release switch immediately after the loading, that is, in the worst case that the reset operation is not performed after the shooting, the focus may be out of focus. There is a nature.

The fourth embodiment of the present invention is an embodiment taking that point into consideration.

The operation of this embodiment will be described with reference to the flowchart of FIG.

FIG. 11 is a flow chart for explaining the processing when the back cover switch 7 of this embodiment changes.

When the state of the back cover switch 7 changes, this flow is started.

First, in S601, it is checked whether the changed state of the back lid is open or closed. If the back lid is open,
The process proceeds to S613, and a known back cover opening process such as clearing of the displayed film counter is performed, and the back cover switch 7 reception process ends.

If the back lid is closed in S601, the flow advances to S602 to check whether the film is put in the cartridge chamber. The presence / absence of the film is detected by whether or not the DX code is detected, a switch that is turned on when the film enters the cartridge chamber, and the like.

If there is no film, it is not necessary to perform any particular operation, and the acceptance processing of the back cover switch 7 is terminated.

If the film is loaded, the routine proceeds to S603, where a known battery check is performed.

Next, in S604, it is checked based on the result of the battery check in S603 whether or not the remaining battery level is sufficient. When the battery level is insufficient, the film loading process cannot be executed, so the acceptance process of the back cover switch 7 ends at this point.

If it is determined in S604 that the battery level is sufficient, the flow advances to S605 to execute a known automatic film loading operation (film loading operation).

Then, in S606, it is determined whether the automatic film loading operation has failed or succeeded. If the automatic loading has failed, the process advances to step S607 to display a warning of automatic loading failure by blinking the film counter or the like. Next, the processing proceeds to S608, and waits until the loading failure warning is released, such as when the back lid is opened and then closed, and then the acceptance processing of the back lid switch 7 ends.

If the automatic film loading is successful in S606, the process proceeds to S609, 1 is set in the film counter stored in the RAM of the microcomputer 6, then the process proceeds to S610, and the film counter set in S609 is reset. Display using an external liquid crystal display.

Next, in S611, the focusing lens 45 is reset.

Finally, in S612, the DX code is read, the ISO sensitivity of the film and the information about the number of films are read, and the acceptance processing of the back cover switch 7 is completed.

In this embodiment, even if the focusing lens 45 is displaced from the standby position before the film is loaded,
Since the focusing lens 45 is returned to the standby position by resetting the focusing lens at the end of the automatic film loading operation started by the back lid closing operation, the first image after the film loading is not out of focus.

<Correspondence between Invention and Example> The “first photoelectric conversion element” in claim 1 is the photoreflector 3 of the example, and the “second photoelectric conversion element” in claim 1 is the example. The photo interrupter 1, which is the "signal detecting means" of claim 1.
Is the “photoelectric conversion element signal processing circuit 5” of the embodiment,
The "film storage portion opening / closing detecting means" is the back cover switch 7 of the embodiment.

Further, the "focusing lens control means" in claim 1 is means constituted by the function represented by steps S203, S208, S211 on the program of the microcomputer 6 of the embodiment.

The "mode setting means" in claim 2 is a means comprising the EEPROM 8 of the embodiment, means inside the microcomputer 6 connected to it, and external terminals.

In addition to the function of claim 1, the "focusing lens control means" of claim 2 further has a function represented by steps S304, S310, S314 in the program.

The "focusing lens control means" of claim 3 has the function shown in step S501 on the program in addition to the function of claim 1.

The "film automatic loading means" of claim 4 is represented by step S605 in the program.

The "focusing lens control means" of claim 4 has a program step S in addition to the above functions.
It has a function represented by 611.

[0153]

According to the first aspect of the present invention, when the back cover is opened, the focusing lens resetting operation is not performed by prohibiting the focusing lens operation including the focusing lens resetting operation. Provided is a camera that is free from the risk of an accident such as biting.

According to the second aspect of the present invention, if the normal photographing mode is set at the time of shipping as a product, the driving of the focusing lens is prohibited when the back cover is opened. No accidents will occur and the focusing lens can be driven in the manufacturing process by setting it to the adjustment operation mode, which allows the focusing lens to be reset with the back cover open. The focus adjustment work in the process can be easily performed.

According to the third aspect of the invention, since the focusing lens can be driven to the storage position even when the back cover is open when the barrier is closed, the camera is not used when the lens is protruding. In addition, the barrier can be closed without any trouble, and there is no risk of impact on the focusing lens.

According to the fourth aspect of the present invention, even if the initial position of the focusing lens becomes incorrect as a result of the focusing lens being left without being reset while the back cover is open before loading the film, Since the focusing lens is reset when the film loading is completed, it is possible to take a focused photograph from the first image after the film is loaded.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a part of an electrical configuration of a camera of a first embodiment of the present invention.

2 is a diagram for explaining a relationship between an output signal of a focus lens driving mechanism of the camera of FIG. 1 and a photo interrupter 3 of FIG. 1 and an output signal of a photoelectric conversion element signal processing circuit 5 of FIG.

3A and 3B are views for explaining the reset operation of the focus lens driving mechanism of the camera of FIG. 1, in which FIG. 3A is an explanatory view when resetting is started when the output of the photo interrupter 3 is a dark signal; 4) is an explanatory diagram in the case of starting resetting when the output signal of the photo interrupter 3 is a bright signal.

FIG. 4 is a flowchart for explaining a resetting operation of the focusing lens in the camera of the first embodiment.

FIG. 5 is a flowchart showing a control operation at the time of shooting by the camera of the first embodiment.

FIG. 6 is a schematic diagram showing a part of the electrical configuration of the camera of the second embodiment of the present invention.

FIG. 7 is a flowchart showing a control operation at the time of shooting by the camera of the second embodiment.

FIG. 8A is a front view of a camera according to a third embodiment of the present invention, showing a state in which the barrier 9 is opened, and FIG. 8B is a front view of the camera in a barrier closed state.

9 is a flowchart showing a control operation of the camera during the barrier opening operation of the camera of FIG.

10 is a flowchart showing a control operation of the camera when the barrier of the camera of FIG. 8 is closed.

FIG. 11 is a flowchart of camera control operation when the back lid is opened and closed in the camera of the fourth embodiment of the present invention.

FIG. 12 is a diagram for explaining a relationship between a focus lens driving mechanism and an output signal of a focus lens position detecting photo interrupter in a conventional camera.

FIG. 13 is a diagram showing a configuration of a photoelectric conversion element signal processing circuit in a camera of the present invention and a conventional technique.

FIG. 14 is a rear view of the essential parts of the film feeding unit in the camera of the present invention and the prior art.

FIG. 15 is a view for explaining the relationship between the arrangement of the photoreflector as the film feed amount detection means of the camera of the present invention and the prior art, the film and the camera back cover, and the output signal of the photoreflector 3; In the figure, (a) shows the case where the output of the photo reflector 3 becomes a dark signal, (b) shows
When the output of the photo reflector 3 becomes a bright signal,
(C) shows when the back cover is opened.

[Explanation of symbols]

1 ... Photointerrupter 1a ... Projector element 1b ... Phototransistor 3 ... Photoreflector 2, 4 ... Constant current source 5 ... Photoelectric conversion element signal processing circuit 6 ... Microcomputer (microcomputer) 7 ... Back cover switch 8 ... EEPRO
M 9 ... Barrier 10 ... Lens barrel 21 ... Film 22 ... Patrone 23 ... Spool 25 ... Perforation 26 ... Back lid 31 ... Comparator 41 ... Shading plate 42 ... Screw shaft 43 ... Stepping motor 44 ... Lens support member 45 ... Focusing lens

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical indication G03B 13/36

Claims (4)

[Claims] 1. A first photoelectric conversion element for detecting a film feeding state, and a second photoelectric conversion element connected in parallel with the first photoelectric conversion element for detecting a focusing lens position. , A signal detecting means for inputting an output signal of the first and second photoelectric conversion elements with a parallel connection point of the first and second photoelectric conversion elements as an input section, and detecting an open / closed state of the film storage section In a camera provided with a film storage unit opening / closing detection unit, a focusing lens control unit is provided which prohibits driving of the focusing lens when the open state of the film storage unit is detected by the film storage unit opening / closing detection unit. A camera characterized by being. 2. A mode setting means for selectively setting a normal operation mode and an adjustment operation mode, and when the adjustment operation mode is set by the mode setting means, the film storage section opening / closing detection means is used. 2. The camera according to claim 1, wherein the focusing lens control means permits driving of the focusing lens even when the film storage portion is detected to be in an open state. 3. A focusing lens having a barrier for protecting the taking lens, and when the barrier changes from the open state to the closed state, the open state of the film storage section is detected by the film storage section opening / closing detection means. 2. The camera according to claim 1, wherein the control means moves the focusing lens to the storage position by permitting driving of the focusing lens. 4. An automatic film loading (automatic film setting) means is provided, and the focusing lens control means performs an initial positioning operation (reset operation) of the focusing lens when the film loading by the automatic loading means is completed. The camera according to claim 1, wherein: