JPH0335230A - In-finder display device - Google Patents

Abstract

PURPOSE:To obtain a large, understandable display advantageous to a built-in space by driving an in-finder display device using the electrooptical elements so that the whole surface of the electrooptical elements becomes high density when a lens barrier is close and becomes low density when the barrier is open. CONSTITUTION:When the lens barrier 5 is left closed, all of display segments 20a - 35a, and 20b - 35b of the elecrooptical elements 15 are displayed at high density. When a opening/closing knob 6 is operated to actuate a lens barrier opening/closing mechanism 42, the lens barrier 5 is opened. When the lens barri er 5 is fully opend, an on-signal is input from a barrier switch 7 to a microcom puter 40. Thus, all of the display segments of the electrooptical elements 15 are instantaneously made transparent via a LCD driver 38, so that a finder image is observable via the segments to find that photographing is possible. Thereby the built-in space need not to be secured separately, and an identifiable, large display is obtained in the limited finder plane.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a display device in a viewfinder of a camera using a transmissive liquid crystal display panel.

[Conventional technology]

Various liquid crystal display devices are used in recent cameras.

Furthermore, as shown in Japanese Patent Application Laid-Open No. 60-102615, there is also known a device in which a liquid crystal display is built into the finder so that display data can be observed along with the subject image.

[Problem to be solved by the invention]

In the conventional viewfinder display device using a liquid crystal display,
The display is installed outside the field of view so that the display does not overlap with the subject image observed through the finder. Therefore, it is necessary to secure space around the viewfinder to incorporate the liquid crystal display, which is disadvantageous in terms of compactness.

[Purpose of the invention]

The present invention has been made in order to solve the problems of the prior art as described above, and provides an in-finder display device that is advantageous in terms of installation space and can display a large and easy-to-understand display. The purpose is to

[Means to solve the problem]

In order to achieve the above object, the present invention disposes a transmissive liquid crystal display panel in the finder optical system so as to cover the finder screen, so that when the lens barrier is closed, the entire surface of the liquid crystal display panel becomes highly concentrated. When the lens barrier is opened, the entire surface of the liquid crystal display panel is driven to have a low concentration.

In addition, a transmissive liquid crystal display board consisting of a plurality of display segments is arranged in the finder optical system so as to cover the finder screen, and the high density pattern of the liquid crystal display board is displayed over time when the shirt release is performed. A configuration in which the high-density pattern of the liquid crystal display panel is sequentially changed, and furthermore, a configuration in which the high-density pattern of the liquid crystal display panel is sequentially changed in conjunction with film feeding is also an effective means for achieving the above object.

[Effect]

As the lens barrier opens and closes, the liquid crystal display panel enters a transparent state or an incompletely transparent state including a light-blocking state, and it is possible to confirm whether the lens barrier is open or closed simply by observing through the finder.

In addition, by changing the high-density display pattern on the liquid crystal display board, a simulated display of the shutter opening/closing operation and film feeding is performed in the viewfinder, which requires almost no space around the viewfinder and is easy to understand even for beginners. The operating status can be displayed.

Embodiments of the present invention will be described below with reference to the drawings.

〔Example〕

In FIG. 2 showing the appearance of a camera using the present invention, a movable lens barrel 3 that can move forward and backward is built into the front of a camera body 2, and when a zoom knob 4 on the back side of the body is operated, it moves forward and backward in the optical axis direction. Change focal length. The movable lens barrel 3 has a built-in zoom lens as a photographing lens, but when not in use, its front surface is covered with a lens barrier 5 as shown in the figure. This lens barrier 5 is configured to cover only the photographic lens, and can be opened and closed by operating an opening/closing knob 6 on the back side of the body. Further, when the lens barrier 5 is opened, the barrier switch 7 is turned on. The camera body 2 further includes a shutter button 8. Projection/reception window for distance measurement9. lO, finder window 11
is provided.

A real-image type finder optical system 12 shown in FIG. 3 is built in the back of the finder window 11. The finder optical system 12 includes, in order from the objective side, a parallax correction prism 13. Objective lens 14. Transmissive liquid crystal display board 15. Porro prism 16. It consists of an array of eyepiece lenses 17. The light flux that has entered the objective lens 14 through the prism 13 forms an image on the entrance surface 16a of the Porro prism 16, and the image is formed on the Porro prism 16. It is observed through the eyepiece 17. Therefore, if a field frame mark or the like is displayed on the incident surface 16a, it is possible to clearly observe the viewfinder image. Furthermore, since the liquid crystal display plate 15 is also placed overlapping the entrance surface 16-a of the Porro prism 16, the image displayed on the liquid crystal display plate 15 can be observed with almost no difference in diopter from the viewfinder image. Ru.

FIG. 1 schematically shows the control circuit of the camera and the display segment arrangement of the liquid crystal display panel 15. As shown in FIG. The transmissive liquid crystal display panel 15 has a total of 32 display panels 1-20a to 35a, 20b to 35b arranged symmetrically.
and is driven by an LCD driver 38. These display segments can be driven independently according to the voltage applied from the LCD driver 38, and are transparent when not driven, and become highly concentrated and almost light-shielded when driven. Note that the LCD driver 38 has a built-in ROM 39, and the ROM 39 stores data for driving the liquid crystal display board 15 in a predetermined display pattern.

The microcopy computer 40 refers to the program stored in the sequence ROM 41 and executes the camera operation sequence, that is, the lens barrier opening/closing mechanism 42. Release switch mechanism 43. AE circuit 44. AF mechanism 45. The shutter drive mechanism 46 controls the operation of the film feeding mechanism 47. In addition, various data used at this time can be accessed from R at any time.
Written to or read from AM48.

The lens barrier opening/closing mechanism 42 opens and closes the lens barrier 5 described above, and manually inputs switching data of the barrier switch 7 associated with the opening/closing to the microcomputer 40 . The release switch mechanism 43 detects the pressing operation of the shutter button 8 and inputs a half-press operation signal and a full-press operation signal to the microcomputer 40. The AE circuit 44 photometers the subject brightness and calculates the shutter speed corresponding to the photometered value. The AF mechanism 45 performs a distance measurement operation in response to a command from the microcomputer 40, and also adjusts the focus of the photographic lens in accordance with the distance measurement signal. The shutter drive mechanism 46 controls the opening and closing of the shank blade according to the shutter time calculated by the AE circuit 44, as will be described in detail later. The film feeding mechanism 47 not only feeds the film each time a photograph is completed, but also rewinds the film after all frames of the film have been photographed.

In FIG. 4 showing the shutter drive mechanism 46, a pair of shutter blades 51a pivotally attached to a shutter substrate 50;
51b has a program shutter that also serves as an aperture,
Each has a slot formed therein. Pins 53a and 53b of the drive ring 52 are fitted into these slots, and when the drive ring 52 rotates clockwise against the spring bias, the shutter blades t151a and 51b
rotates in the opening direction, and when the drive ring 52 reverses, each rotates in the closing direction.

The drive ring 52 is rotated by a stepping motor 56 via a gear train 54 and a gear train 55 formed in a portion thereof.

Further, as shown in the figure, in the closed state, the shutter blade 51a
, 51b partially overlap, and the drive ring 52
Exposure is started at the moment when the pin 57, which is attached to one of the shutter blades 511), rotates a predetermined amount and turns on the timing switch.

Stepping motor 56 is driven by motor driver 60. The motor driver 60 receives from the microcomputer 40 a driving clock pulse CK as well as a PF multiplied signal PR signal for determining the rotation direction. Then, when the PF multiplier signal "IJ, -PR signal" is "0", the stepping motor 56 rotates forward and the jasitter blade 51
a, 51b are rotated in the opening direction, and the PF multiplied signal rOJ,
When the PR signal is rlJ, the shutter blade 51a.

51 is rotated in the closing direction. Note that when both the PF and PR signals are "0", the stepping motor 56 stops;
Rotation of the shutter blade also stops.

The shutter display counter 62 is cleared to the count value rQj at the moment the timing switch 58 is turned on, and then the count value is increased by a timer interrupt every 50 msec, which will be described later.

In FIG. 5 showing the film feeding mechanism 47, a motor 66 is built inside a rotatable take-up spool 65. The driving force of this motor 66 is
7 to a fork 69 for rotating the take-up spool 65 or the winding shaft 68a of the cartridge 68. As is well known, the feed transmission mechanism 67 has a built-in gear train, a clutch, etc. When the film 70 is wound up, the motor 66 rotates in the normal direction to drive the take-up spool 65, and when the film 70 is rewound, the motor 66 rotates forward to drive the take-up spool 65. The motor 66 is reversely rotated and the fork 69 is driven.

The motor 66 is driven by a motor driver 71. The motor driver 71 has a micro combination unit 40.
MF and MR signals for rotation control are supplied from

Then, the MF signal is "1".

When the M R signal is “0”, the motor 66 rotates forward and the MF
When rOJ is rOJ and the MR signal is "1", the motor 66 rotates in reverse. Further, when both signals are rQJ, the driving of the motor 66 is stopped.

A driven sprocket 72 is engaged with the perforation 70a of the film 70, and is driven to rotate when the film 70 is fed in the winding direction or the unwinding direction. As shown in FIG. 6, the driven sprocket 72 has eight teeth 72a that engage with the bar fore 70a, and rotates exactly once while the film 70 is fed one frame.

Further, the driven sprocket 72 is integrally provided with eight conductive pieces 72b corresponding to the number of teeth, and during one rotation of the driven sprocket 72, eight conductive pieces 72b are connected to the feed detection switch 73 by the conductive pieces 72b. A feeding pulse is output. This feeding pulse is input to the microcomputer 40, and its number is counted by the perforation counter 75.

The perforation timer 76 is cleared every time the feed pulse is output, and measures the time until the next feed pulse is output from the feed detection switch 73.

The operation of the camera having the above configuration will be explained below.

The flowchart in FIG. 8 shows display processing associated with opening and closing of the lens barrier 5. When the lens barrier 5 remains closed, the display segment 20 of the liquid crystal display panel 15
All of a to 35a and 20b to 35b are displayed in high density, and the viewfinder screen is completely black, making it possible to confirm through the viewfinder that photography is not possible. When the opening/closing knob 6 is operated to operate the lens barrier opening/closing mechanism 42, the lens barrier 5 is opened, and when the lens barrier 5 is fully opened, an ON signal is input from the barrier switch 7 to the microcomputer 40. As a result, the microcomputer 40
Since all the display segments of the liquid crystal display panel 15 are momentarily made transparent via the LCD driver 38, the finder image can be observed through this, and it can be seen that the camera is ready for photographing. Furthermore, since the liquid crystal display panel 15 is divided into a plurality of display segments, the lens barrier 5
It is also possible to change the display of the liquid crystal display segments so as to approximate the opening and closing operations of the LCD.

FIG. 8 shows the overall camera operation sequence after the lens barrier 5 is opened. When a half-press signal of the shutter button 8 is inputted to the microcomputer 40 via the release switch mechanism 43, the microcomputer 40 outputs operation command signals to the AE circuit 44 and the A1 mechanism 45, respectively. The AE circuit 44 calculates the exposure time of the program shutter in accordance with the subject brightness. The program shutter has two modes: one is the so-called triangular exposure mode, in which the aperture diameter increases as the exposure time elapses in response to the brightness of the subject, and then the shutter closes. It operates in either the trapezoidal exposure mode in which it enters a closing operation after being held for a predetermined time, but when calculating the exposure time described above, the aperture diameter is held at a predetermined aperture diameter for a time S^ in which the aperture diameter gradually increases. Both of the three times are calculated. Of course, in triangular exposure mode,
St=OJ. Further, after the exposure time calculation process, distance measurement is performed by the A1 mechanism 45, and object distance data is obtained. Note that the exposure time data and subject distance data are each fed back to the microcomputer 40 and stored in a predetermined address position of the RAM 48.

When the shutter button 8 is subsequently pressed fully, the microcomputer 40 receives a full press signal from the release switch mechanism 43 and starts a photographing sequence. At the start of the photographing sequence, the A1 mechanism 45 is first activated, and the RAM
The photographing lens is set to a focus position corresponding to the subject distance data stored in 4B. Thereafter, the shutter drive mechanism 46 is activated to perform exposure. Of course, during this exposure process, the exposure time data in the RAM 48 is referenced to control the rotation of the stepping motor 56. Once the exposure is complete, the photographic lens is reset to its initial position, and then
The film feeding mechanism 47 operates to feed the film one frame, thereby completing one shooting sequence.

Next, the processing when the shutter drive mechanism 47 is activated and the display function of the liquid crystal display panel 15 will be explained with reference to FIGS. 9 to 12. Immediately before the shutter button 8 is fully pressed, as long as the lens barrier 5 is open, the liquid crystal display panel 15 is completely transparent as shown in FIG. 12, and the entire viewfinder image can be observed. . The shutter button 8 is T in FIG. It is fully pressed at the point in time, and the fully pressed signal is sent to the microcomputer 4.
0, the microcomputer 40 holds this full press signal as a release signal until exposure is completed.

When the release signal is generated, the microcomputer 4
The shutter display counter 62 is set to "0" by the signal from "0".
”, allowing timer interrupts for display processing. In addition, the microcomputer 40
PF multiplier signal “1” supplied to the motor driver 60 from
Then, the stepping motor 56 starts normal rotation. When the scanning motor 56 rotates forward by a predetermined amount, a pinhole is formed by the shutter blades 51a and 51b, and exposure is started.

At the moment when this exposure starts, the timing switch 58 is turned on, and from this point on, measurement of a time S is started, and the stepping motor 56 continues to rotate normally during that period. Therefore, the shutter blade 51a.

51b performs exposure while gradually increasing the aperture diameter. After the elapse of time SA, the PF multiplier signal changes from “1” to “
Then, both the PF multiplication signal and the PR signal become "0", and the driving of the stepping motor 56 is stopped. At the same time, measurement of time S is started. Therefore, until the time S passes, the shutter blades 51a, 51
b maintains a constant aperture diameter, thereby performing exposure in trapezoidal exposure mode. Of course, AE circuit 4
As a result of the exposure time calculation in step 4, when rsB=oJ, time measurement of time S8 is not performed, and exposure is performed in the triangular exposure mode.

When the measurement of time Ss is completed, the PR signal becomes rlJ and the stepping motor 56 starts rotating in reverse. At the same time, the shutter blades 51a and 51b rotate in the closing direction, and the exposure is completed the moment the timing switch 58 is turned off. Even after the tie/f edge 58 is turned off, the stepping motor 56 is reversed for a time S0, after which the PR signal also becomes "0" and the Yatta blades 51a and 51b are restored to their initial state.

During the drive control of the stepping motor 56 described above, the timer interrupt process is repeated every 50 msec,
The shank display counter 62 performs a counting operation every time this is repeated. Then, when the count value reaches "5", the timer interrupt is disabled and the process is completed.

While the count value of the shutter display counters 6, 2 increases as shown in FIG. 10, the display shown in FIG. 12 is performed on the liquid crystal display board 15 in accordance with the count value.

The pattern P1 is displayed on display segments 20a and 20b.
, 22a, 22b are displayed at high density, and the pattern P2 is further displayed by displaying the display segments 21a, 21
b, 23a, 23b, 25a, 25b, 26a, 26b
, 29a, 29b, 30a, 30b, 35a, and 35b are displayed in high density. Also pattern P
.

-As can be seen from the change in the high-density display pattern in FIG. 12, this is a simulated display of the shutter closing operation. Actively hiding the finder screen in this way to display the shutter operation and prohibition of the release operation is very easy to understand and is very advantageous in terms of saving display space.

When the simulation display of the shutter closing operation is finished, the liquid crystal display board 15 is completely black (pattern P).
It becomes. Then, in synchronization with the film feeding after the exposure display, a simulated display of film feeding is started.

One-frame feeding of the film by the film feeding mechanism 47 is performed according to the flowchart shown in FIG.

When the exposure completion signal is fed back from the shutter drive mechanism 46 to the microcomputer 40, the MF is supplied from the microcomputer 40 to the motor driver 71.
The signal becomes "1" and the count values of the perforation counter 75° and perforation counter 76 are cleared to r□.

When the MF multiplier signal becomes "l", the motor 66 starts rotating normally via the motor driver 71, the film 70 is fed in the winding direction, and the driven sprocket 72 rotates in conjunction with the film feeding. As the driven sprocket 72 rotates, when the contact piece of the feed detection switch 73 comes into contact with the conductive piece 72b, the feed detection switch 73 outputs a feed pulse.

This feeding pulse is counted by a perforation counter 75 via the microcomputer 40, and a feeding display, which will be described later, is performed in accordance with the counted value. and,
The count value of perforation counter 75 is "8"
When the MF multiplier signal reaches "1", the MF multiplier signal "1" changes to "0" and normal rotation of the motor 66 is stopped. This completes one frame advance of the film, and the camera enters a standby state for the next shooting.

After the motor 66 starts normal rotation, the feeding pulse is e.g.
If the perforation timer 76 detects that the film is not output for more than a second, it means that it is impossible to wind the film any further, and in this case, the liquid crystal display panel 15 displays a completely black display. Then, for example, by referring to the value of the film frame number counter, when all the frames of the film 70 have been photographed, the film rewinding process may be automatically started.

The flowchart in FIG. 14 shows display processing during film feeding, and the display pattern shown in FIG. 15 is displayed on the liquid crystal display board 15 in correspondence with the count value of the perforation counter 75.

That is, the transparent range within the finder screen gradually expands in accordance with the amount of film 70 fed, and becomes completely transparent when one frame feeding is completed.

In this way, when the liquid crystal display panel 15 becomes fully transparent and the entire viewfinder image can be observed, the next photograph can be taken. This allows for easy-to-observe display in the viewfinder.

Although the explanation has been made according to the illustrated embodiment, various other patterns and arrangements of the display segments of the liquid crystal display panel 15 can be adopted.
As shown in the figure, a matrix arrangement of minute display segments 80a can also be used. Regarding the film feed display, for example, a vertical stripe of a predetermined width extending up and down the viewfinder screen may be moved from left to right in accordance with the amount of film feed, or the top or bottom half of the finder screen may be gradually moved. It is also possible to create a display that widens the transparent range.

Furthermore, when displaying at high density on a liquid crystal display board, the display does not necessarily have to be in a completely light-shielded state, and the finder optical system incorporating the liquid crystal display board is not necessarily limited to a real image type.

〔Effect of the invention〕

As described above, according to the viewfinder display device of the present invention, a transmissive liquid crystal display panel is arranged to cover the viewfinder screen, and the density display is changed in response to opening and closing of the lens barrier. You can tell at a glance whether it is acceptable or not.
Furthermore, there is no need to secure a separate 4° space for incorporating the liquid crystal display panel.

In addition, a transmissive liquid crystal display board consisting of multiple display segments is arranged within the finder optical system to cover the finder screen, and the high density display pattern on the liquid crystal display board is sequentially changed to control shutter operation and film feeding operation. Since the simulated display is used, it is possible to display a large display that is easy to identify even within the limited viewfinder screen, and it is also possible to monitor and observe the operational status of the camera mechanism through the viewfinder.

[Brief explanation of drawings]

FIG. 1 is a block diagram schematically showing the circuit configuration of a camera to which the present invention is applied. FIG. 2 is an external view of a camera to which the present invention is applied. FIG. 3 is a perspective view showing an example of a finder optical system. FIG. 4 is a schematic diagram of the shutter drive mechanism. FIG. 5 is a schematic diagram of the film feeding mechanism. FIG. 6 is a perspective view showing an example of a driven sprocket. FIG. 7 is a flowchart showing the opening/closing process of the lens barrier. FIG. 8 is a flowchart showing sequence processing when a release operation is performed. FIG. 9 is a flowchart showing processing by the shutter drive mechanism. FIG. 10 is a tie chart showing the operation of the shutter drive mechanism. FIG. 11 is a flowchart showing the display processing of shutter operation. FIG. 12 is an explanatory diagram showing a display pattern of shutter operation. FIG. 13 is a flowchart showing the processing by the film feeding mechanism. FIG. 14 is a flowchart showing the display processing of film feeding. FIG. 15 is an explanatory diagram showing a display pattern for film feeding. FIG. 16 is a conceptual diagram showing another example of a liquid crystal display board. 12.Finder optical system 15..Liquid crystal display board 20a to 35a, 20b to 35b-.Display segment 40..Microcomputer 51a, 51b..Shutter blade half length 5 days..Timing switch 62..Shutter display counter 72 ... Driven sprocket 73 ... Feed detection switch 75 ... Perforation counter. Figure 2 Figure Figure 747 (Film nL stirring structure) Figure 7 Figure 11 Figure 12 Figure 15 Meat 13 Figure 16 Figure procedure amendment 2゜3゜4゜Name of invention Display device in finder Relationship with the case of the person making the amendment Patent applicant

Claims (3)

[Claims] (1) In a camera equipped with a lens barrier that opens and closes the front surface of the photographic lens, a transmissive liquid crystal display board is arranged within the viewfinder optical system to cover the finder screen, and when the lens barrier is closed, the entire surface of the liquid crystal display board is What is claimed is: 1. A viewfinder display device characterized in that the display device is driven so that the liquid crystal display panel has a high concentration, and when the lens barrier is opened, the entire surface of a liquid crystal display panel is driven so that the concentration is low. (2) A transmissive liquid crystal display board consisting of a plurality of display segments is arranged in the finder optical system so as to cover the finder screen, and a high density pattern on the liquid crystal display board is displayed over time when the shutter release is performed. An in-finder display device characterized in that the display changes sequentially. (3) A transmissive liquid crystal display board made up of multiple display segments is arranged in the finder optical system so as to cover the finder screen, and the high density pattern of the liquid crystal display board is sequentially changed in conjunction with film feeding. A viewfinder display device characterized in that: