JP3125810B2 - Display drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display driving device for driving a display device such as a liquid crystal panel (hereinafter abbreviated as LCD) for displaying an operation state of electronic equipment.

[0002]

2. Description of the Related Art In recent years, information to be displayed has been increasing in electronic devices such as cameras and personal computers. Therefore, the amount of information that can be displayed is increased without increasing the size of the electronic device itself. That is urgent.

In order to achieve this object, in the past, the driving of the LCD, which has been a static system in the past, has almost been replaced by the dynamic system. This dynamic method is a method in which the lighting or extinguishing of a plurality of segments is controlled on the same line by utilizing the multiplexing of drive signals, that is, the use of the periodic level of the drive voltage value. According to this method, the number of displayable segments can be increased without increasing the number of electrodes of the LCD. In this case, the duty ratio is called １ ／ or the like in accordance with the number of segments that a single electrode covers.

In extreme applications, as a further development of the dynamic system, a display system called a dot matrix in which the display form can be arbitrarily changed by the drive circuit without being influenced by the shape of the segment is often used. ing. This method is a method in which an LCD is composed of segments of square points arranged regularly on the entire surface of a panel, and the LCD is driven by electrodes arranged in a matrix in a matrix. In this method, a high duty ratio of 1/64 or more is usually employed.
This duty ratio tends to be set higher in the future for both the dynamic system and the dot matrix system.

On the other hand, the LCD has temperature dependency and viewing angle dependency. The principle of an LCD is controlled by a voltage value applied to turn on and off the LCD, but its threshold level has a property of changing with temperature. Therefore, if the multiplexed drive voltage is always constant, the boundary between display and turn-off changes due to a change in environmental temperature. Specifically, a phenomenon occurs in which a segment to be turned off is turned on at a high temperature, and a segment to be turned off is turned off at a low temperature. Also, LC
Since D uses polarized light, the boundary between turning on and off the segments changes depending on the viewing angle.

In order to solve such temperature dependence and viewing angle dependence, it is only necessary to change the driving voltage value, that is, the bias value. Therefore, the conventional display driving device is provided with a dial outside the device, and A method has been adopted in which the rotation is linked to the value of the semi-fixed resistance, and the adjustment is left to the user himself. Further, as a display driving device that solves only the temperature dependency, there is a display driving device in which a thermistor or the like is provided in a part of a driving circuit and a certain degree of temperature correction is automatically performed.

[0007]

However, in the above-mentioned conventional display driving device, the bias value is changed by turning the dial each time the user changes the environmental temperature and the viewing angle, and the adjustment is performed so that the image looks optimal. I had to.

Further, in the latter display drive device for automatically performing temperature correction, the temperature range in which the operation is effective is narrow, and fine adjustment must be performed every time the viewing angle is changed.

In particular, the camera is expected to be frequently adjusted since the temperature range used is very wide unlike ordinary office equipment. However, there is a possibility that an important photo opportunity is missed due to the adjustment work.

An object of the present invention is to solve the above-mentioned problems and to provide a display driving device capable of automatically optimizing the appearance of the display means according to the user's preference.

[0011]

In order to solve the above-mentioned problems, a display driving apparatus according to the present invention comprises an electro-optical display means (6) and a bias value generating means for generating a bias value for the electro-optical display means. Means (23) and changing means (7, 2) for changing the bias value generated by the bias value generating means.
8), storage means (22) for storing a plurality of bias values changed by the change means, and storage contents of the storage means.
Updating means (26) for updating to include the latest changed bias value changed by the changing means, calculating means (26) for performing arithmetic processing on the updated plurality of bias values stored in the storage means, Control means (26) for causing the bias value generation means to generate a bias value based on the operation result of the means.

[0012]

[0013]

According to the present invention, a plurality of changed bias values are stored, and a bias value obtained by performing arithmetic processing on the bias values is applied to the electro-optical display means. The display (the degree of appearance) of the optical display means can be automatically optimized.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments will be described below with reference to the drawings.
This will be described in more detail. FIG. 1 is an external view showing an embodiment of a display driving device according to the present invention. The display drive device of this embodiment is applied to a single-lens reflex camera 1. A lens 2 is mounted on the camera 1, the subject is confirmed by a finder 4, and then exposure is performed by pressing a shutter button 3.

A back cover 5 is attached to the back of the camera 1, and an LCD 6 is provided on the back cover 5. The LCD 6 displays a proper exposure condition and the like for the subject, which is photometrically calculated by the camera 1, and is driven by a dot matrix method.

On the back cover 5, density adjustment buttons 7 and 8 are provided beside the LCD 6. The density adjustment buttons 7 and 8 are buttons for adjusting the display density of the LCD 6. When the density adjustment button 7 increases the display density of the LCD 6, the density adjustment button 8 decreases the density. Sometimes used. In this embodiment, the density adjustment of the LCD 6 is automatically performed finally, but the density adjustment buttons 7 and 8 are used for inputting conditions including the photographer's preference.

In the camera 1, a plurality of mercury switches 9 are provided inside the viewfinder 4 so as to have a predetermined angular relationship. Here, the mercury switch 9 is a switch that detects the attitude of mercury sealed in a glass tube when the mercury switch contacts an internal electrode. By arranging a plurality of the mercury switches 9 inside the camera 1 so as to have a predetermined angular relationship as shown in FIG. 1, the attitude of the camera 1 to which the mercury switch 9 is attached can be detected. . Examples of the detected posture include a normal position, a vertical position, an inverted position, and the like.

The mercury switch 9 detects the posture of the camera 1 and is incorporated in the judgment processing of the multi-segment photometry. By judging the top and bottom of the camera 1, the accuracy of the proper exposure is improved. And known. In this embodiment, as will be described later, the attitude detecting means using the mercury switch 9 is used for correcting the viewing angle dependence of the LCD.

FIG. 2 is a block diagram showing an embodiment of the display driving device according to the present invention. In FIG. 2, camera 1
And the electric circuit inside the back cover 5, the camera 1 on the left side and the back cover 5 on the right side from the two-dot chain line.

First, the configuration of the camera 1 will be described. The CPU 14 includes a luminance signal relating to the subject from the photometry circuit 11, a sensitivity signal of the film being used from the film sensitivity detection circuit 12, an operation signal of the shutter button 3 from the switch detection circuit 13, and an internal signal of the camera 1. Various switch signals that represent the progress of the sequence
Each is connected.

An output from the CPU 14 is transmitted through a drive circuit 15 to a shutter 1 for exposing the film to the film for a predetermined time.
6, an aperture 17 for controlling the amount of light passing from the lens 2 to the film, and a winding motor 18 for winding the film by one frame after exposure are operated. Also, CP
U14 transmits a display signal and the like to the CPU 26 in the back cover 5 through a plurality of contacts (not shown).

Next, the configuration of the back cover 5 will be described. C
The PU 26 has a density adjustment signal of the LCD 6 from one of the density adjustment buttons 7 and 8, a posture signal of the camera 1 from the plurality of mercury switches 9, a display signal from the CPU 14 described above, and a signal from the temperature detection circuit 21. And the LCD density signal from the storage circuit 22 are connected. Here, the storage circuit 22 has a bidirectional signal transfer format,
In addition to outputting an LCD density signal to the PU 26,
The LCD density signal from U26 may be input.

The output signal of the CPU 26 drives the LCD 6 via a drive circuit 25,
Control the output voltage. Conventionally, density adjustment has been performed by a semi-fixed resistor that is manually variable or a thermistor whose resistance value changes according to temperature. In this embodiment, a DA converter 24 is used.

The DA converter 24 includes a plurality of resistors 2
A ladder resistor 23 composed of 3a to 23n;
Since the upper end of the ladder resistor 23 is fixed by the power supply voltage (not shown) and the lower end is fixed by the output of the DA converter 24 as described above, the divided voltage between the resistors 23a to 23n is determined by the output of the DA converter 24. Will be controlled by Further, the divided voltage output between the resistors 23a to 23n is input to the drive circuit 25 and is incorporated in the drive waveform for the LCD 6.

Next, the operation of the display driving device of this embodiment will be described. FIG. 3 is a flowchart illustrating a processing routine of the CPU of the camera to which the display driving device according to the embodiment is applied. The execution of this processing routine is started when the CPU 14 is powered on. The CPU 14 inputs a subject luminance signal from the photometry circuit 11 (step 30), and after inputting a film sensitivity signal from the film sensitivity detection circuit 12 (step 31), performs appropriate exposure based on the subject luminance signal and the film sensitivity signal. Calculate conditions (Step 3
2). Next, the CPU 14 transmits display data corresponding to the appropriate exposure condition to the CPU 26 of the back cover 5 (step 33).

Here, the CPU 14 operates the shutter button 3
It is detected whether or not a release switch (not shown) is turned on by the operation (step 34). If the release switch has not been turned on, the process returns to step 30 and repeats the above routine. When the release switch is turned on, the mirror (not shown) is retracted from the optical path (step 3).
5), the aperture 17 is set to a predetermined value (step 36),
By opening the shutter 16 for a predetermined time (step 3
7) Project the subject light onto the film. After the exposure, the motor 18 is rotated to wind up one frame of the film, and the mirror, the diaphragm 17 and the like are restored (step 38). Thereafter, the process returns to step 30,
Repeat the above routine.

FIG. 4 is a flowchart showing a processing routine by the CPU in the back cover of the camera to which the display driving device according to the embodiment is applied. This process starts when the CPU 26 is turned on. The CPU 26 waits for display data to be transmitted from the camera 1 (step 40), and stores the transmitted display data in the storage circuit 22 (step 41). The storage location is the RAM inside the CPU 26.
(Not shown).

Next, the CPU 26 averages the density data D ** in the table classified for each posture and each temperature in the storage circuit 22 stored at the time of the previous operation, and obtains the average density data D *. 0 is calculated (step 42). Details will be described later in Table 1.

Further, the CPU 26 inputs the current temperature detected by the temperature detecting circuit 21 (step 43).
Next, the attitude of the camera 1 detected by the mercury switch 9 is input (step 44). Steps 43 and 44
The D / A converter 24 is driven by the density data optimal for the temperature and the attitude input in step (2), that is, the average density data D * 0 calculated in step (step 45).
Then, the display data once stored in step 41 is output to the drive circuit 25, and the segments in the LCD 6 are selectively turned on (step 46).

Next, the CPU 26 determines whether or not the density adjustment button 7 is turned on and an operation for increasing the density is performed (step 47). On the other hand, it is determined whether or not the density adjustment button 8 is turned on and an operation to lower the density is performed (step 48).

Density adjustment button 7 or density adjustment button 8
If the above operation is performed, D * 0 is changed by incorporating the adjusted density data (step 49). This means that the driving based on the average density data D * 0 in step 45 is replaced with the manually adjusted driving data only in this case. And D
The A converter 24 is driven by the changed density data D * 0 (step 50).

The CPU 26 drives the drive circuit 25 based on the display data once stored in step 41 or step 56 described later (step 51). Thus, the density of the LCD 6 is adjusted.

Here, it is determined whether or not the operation of the density adjustment button 7 or the density adjustment button 8 has been interrupted (off) (step 52). If it remains on, step 49
Are repeated, and the density of the LCD 6 is continuously changed.

Density adjustment button 7 or density adjustment button 8
Is turned off, the stored density data is moved up line by line (step 53). First, D * 2 is
* 1, and finally the manually adjusted density data D * 0 is incorporated into D * 5 (step 54). Here, the data in D * 0 is not erased but copied to D * 5. In steps 55 and 56, as in steps 40 and 41, data reception and data storage are performed.

[0035]

[Table 1]

Next, a more specific description will be given with reference to Table 1. Table 1 is a table showing a part of the density data map in the storage circuit 22. First, “normal position”, “vertical position”, “inverted position”, and the like are prepared as major categories as posture types. In addition, each major category has a temperature range of “−20”.
° C or lower ”,“ -20 ° C to 0 ° C ”,“ 0 ° C to +20 ”
° C ”and“ + 20 ° C or higher ”are prepared as minor classifications. In each of the sub-classes, data 1 to data 5 are stored as five raw data, and data 0 is stored as average data of five raw data or manually adjusted data.

As a representative example, Table 1 shows only the map of the "normal position". The processing in Table 1 will be described below in association with each step in FIG. Here, for ease of explanation, the posture is “normal shooting” and the temperature is “+ 20 ° C. or more”.
And

First, at step 49, the latest density data manually adjusted is incorporated into D40. D40 is adopted for display driving in the subsequent step 50. In steps 53 to 54, the oldest data D41 is discarded.
Instead, incorporate D42, incorporate D43 into D42, incorporate D44 into D43, and incorporate D4 into D45.
A process for incorporating 0 is performed. That is, by moving up each data, it is updated as the latest data collection. At this time, D40 which is the newest data exists as it is as D41. The above processing is executed for the portion relating to the posture and temperature at that time when the density change buttons 7 and 8 are turned on. In step 42, the values of data 0 are obtained by averaging the numerical values of data 1 to data 5 for all the sub-classes. Since this is immediately after the start of the operation, the LCD 6 must be displayed first, but the optimum density condition is set as an average value of data 1 to data 5 accumulated in the past.

In the embodiment described above, the data amount is set to five for ease of explanation, but the processing may be performed with more data. In addition, in order to obtain the optimum bias value, an average value may be an arithmetic mean or a square mean. When the mean square is used, the preference of the user appears more remarkably. Further, the maximum value and the minimum value may be excluded. In this way, data in an extreme usage environment can be excluded. Furthermore, the optimum value may be obtained based on other statistical processing such as weighting. In this embodiment, the method of changing the output value of the D / A converter to change the bais value of the LCD has been described. However, any method may be used as long as the bias value of the LCD can be optimized. .

[0040]

As described above, according to the present invention, based on a plurality of data according to the user's preference,
Since the appearance of the electro-optical display means is automatically optimized, it is possible to eliminate the extra work of turning the adjustment dial to change the bias value each time the device is used and adjusting the appearance. Therefore, in the case of the camera, the photographing information can be immediately confirmed together with the photographing preparation operation, so that an important photo opportunity is not missed.

[Brief description of the drawings]

FIG. 1 is an external view showing an embodiment of a display driving device according to the present invention.

FIG. 2 is a block diagram showing an embodiment of a display driving device according to the present invention.

FIG. 3 is a flowchart illustrating a processing routine of a CPU of a camera to which the display driving device according to the embodiment is applied.

FIG. 4 is a flowchart showing a processing routine by a CPU in a camera back lid to which the display driving device according to the embodiment is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Camera 2 Lens 3 Shutter button 4 Viewfinder 5 Back cover 6 LCD 7,8 Density adjustment button 9 Mercury switch 11 Photometry circuit 12 Film sensitivity detection circuit 13 Switch detection circuit 14 CPU 15 Drive circuit 16 Shutter 17 Aperture 18 Winding motor 21 Temperature Detection circuit 22 Storage circuit 23 Resistance ladder 24 DA converter 25 Drive circuit 26 CPU

Claims (7)

(57) [Claims] 1. An electro-optical display device, a bias value generating device for generating a bias value for the electro-optical display device, and a bias value generated by the bias value generating device.
Changing means for changing ; storing means for storing a plurality of bias values changed by the changing means; and changing the storage contents of the storing means by the changing means.
Updating means for updating to include the latest changed bias value
And the updated plurality of buffers stored in the storage means.
Calculating means for performing arithmetic processing on the bias value, and a bias value based on a calculation result of the calculating means.
A display driving device, comprising: a control unit for causing the bias value generation unit to generate the bias value . 2. The method according to claim 1, wherein the changing unit sets the bias value to an arbitrary value.
It is a manual adjustment means that can be adjusted to the value of
The display driving device according to claim 1. And detecting the ambient temperature of said electro-optical display means.
A temperature detecting unit for detecting the temperature of each of the plurality of predetermined temperature classifications.
In addition, the corresponding bias values can be stored respectively, and
The bias value corresponding to each temperature class is
A plurality of temperature control means for detecting the temperature detected by the temperature detection means.
And a bias based on the calculation result by the calculation means.
Generating the bias value by the bias value generating means.
The display driving device according to claim 1, wherein 4. An electro-optical display means for detecting an attitude of said electro-optical display means.
The storage means further comprises a plurality of posture classifications defined in advance.
In addition, the corresponding bias values can be stored respectively, and
The bias value corresponding to each posture classification is
And the control unit is configured to detect the posture detected by the posture detection unit.
And energizing, bias based on the calculation result by the calculating means
Generating the bias value by the bias value generating means.
The display driving device according to claim 1, wherein 5. The computer according to claim 1 , wherein said calculating means is stored in said storing means.
Among the multiple bias values, the newer bias value is larger.
3. A method according to claim 1, wherein weighting is performed.
Item 5. The display driving device according to any one of items 4. 6. The computer according to claim 1 , wherein said calculating means is stored in said storing means.
The mean or arithmetic mean of multiple bias values
The method according to any one of claims 1 to 4, wherein
4. The display driving device according to 1. 7. The computing means according to claim 1 , wherein
Exclude maximum and / or minimum bias values
The arithmetic processing is performed by using
The display driving device according to claim 6.