JPH0974497A - Display device having provision for multi-frequency - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain external control by storing on/off information when a display input signal is controlled by automatic pattern adjustment function and not adjusting the automatic screen processing in the case of off-information even when changeover is detected. SOLUTION: A system microcomputer 10 discriminates detection of display input signal frequency according to a voltage proportional to a horizontal frequency and synchronization polarity information at a synchronization discrimination circuit 6 and contents of an EEPROM 12 are read and data in matching with the signal are transferred. Upon receipt of an automatic screen adjustment function OFF command from a main body key/remote control section 11, conduction of automatic screen adjustment processing is forcibly stopped. When it is discriminated that another input signal is received from synchronization discrimination data fed from the synchronization discrimination processing section 6 to the system microcomputer 10, the function information is read out of the ROM 12. When the information indicates OFF information, no automatic screen adjustment processing is conducted, and when information indicates ON information, the automatic screen adjustment processing is conducted, corresponding signal data are read out of the ROM 12 to execute video image control processing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-frequency compatible display device having an automatic screen adjustment function, and more particularly to a multi-frequency compatible display device having a control function for the automatic screen adjustment function.

[0002]

2. Description of the Related Art Conventionally, this kind of multi-frequency compatible display device improves the usability of the user by providing a display screen position and amplitude corresponding to display input signals having various scanning frequencies. There is.

For example, in Japanese Patent Laid-Open No. 1-314291, a means for storing a display adjustment state corresponding to various sync signals and a means for detecting a sync signal cycle of an input display signal correspond to the detected scanning frequency. A technique is described in which a display adjustment state is read from a storage destination and a circuit to be adjusted of a display device is controlled to cope with display signals having different scanning frequencies.

[0004]

Since the conventional multi-frequency compatible display device with automatic screen adjustment function does not have a control means for the automatic screen adjustment function, it fluctuates like a reproduced video signal of a VTR as a display input signal. When a signal such as (hereinafter referred to as jitter) is input, it may be detected that the display input signal has been switched, and the adjustment state of the screen may be changed. In addition, the malfunction of the automatic screen adjustment function can be prevented by using a time base corrector (hereafter TBC), which is conventionally used to suppress fluctuations in the video signal to characteristics that conform to the standard. Although it is prevented, there is a problem that the circuit scale becomes large when the TBC is used.

[0005]

In order to solve the above-mentioned problems, in the display device with an automatic screen adjustment function of the present invention, the allowable range of the sync signal cycle and the information of the display adjustment state corresponding to this sync signal cycle are provided. The screen adjustment data storage means that stores the information, the automatic screen adjustment control information storage means for enabling / disabling the automatic screen adjustment function for each type of synchronization signal, and storing the information, and the automatic screen adjustment from the command input means. When a function control command is input, it is checked whether the input signal for display is a signal capable of controlling the automatic screen adjustment function, and if the automatic screen adjustment function can be controlled, the automatic screen adjustment function control means for controlling the automatic screen adjustment function It has and.

[0006]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention, and is a block diagram of a signal processing circuit of a multi-frequency compatible liquid crystal projector. FIG. 2 is a flowchart of the automatic screen adjustment processing executed by the multi-frequency liquid crystal projector device according to the first embodiment of this invention. FIG. 3 is a schematic diagram of signal data storage contents of the multi-frequency compatible liquid crystal projector device according to the first embodiment of the present invention.

The signal processing circuit portion of FIG. 1 includes a clamp amplifier circuit 1, an A / D conversion circuit 2, a signal processing G / A circuit 3, and a D / A.
The conversion circuit 4, the drive amplification circuit 5, the synchronization determination circuit 6, the timing G / A circuit 7, the VCO (Voltage Content)
roll Oscillator) 8, PLL circuit (Ph
It is composed of an assembling locked loop 9 and a system microcomputer circuit 10. The input signals are video signals R / G / B, horizontal synchronizing signal H, and vertical synchronizing signal V.
5 inputs in total.

The clamp amplifier 1 amplifies the input signal,
The signal level is required for the A / D conversion circuit 2. The signal processing G / A circuit 3 mainly includes a black level shift section that sets a black level, a contrast adjustment section, a matrix section that corrects color reproducibility, and V which is a voltage-transmittance characteristic of the liquid crystal panel.
It is composed of a VT correction unit for correcting the -T characteristic, a bright adjustment unit, an AC drive unit for inputting a signal to the panel by AC, and the like. The A / D conversion circuit 2 converts an analog signal into a digital signal for digital processing in the signal processing G / A 3, and the D / A conversion circuit 4 is a digitally processed signal because the panel driver IC is an analog driver. Is a circuit unit that is converting into analog again.

The sync discriminating circuit 6 changes the frequency (F) / voltage (V) of the horizontal frequency of the input horizontal sync signal, vertical sync signal or composite sync signal into a F / V converted voltage and a sync polarity depending on the polarity. Output as a logic signal. The timing G / A 7 outputs a reference timing signal of a horizontal cycle according to a clock (main clock) input with the data from the system microcomputer 10. The VCO 8 is controlled by inputting the signal and the horizontal synchronizing signal of the input signal to the PLL circuit 9 so that the frequency of the main clock matches the dot clock frequency of the input signal. As a result, the RGB signal is sampled at the dot clock frequency, so that the RGB signal can be faithfully reproduced. Furthermore, each A
The / D conversion circuit 2, the D / A conversion circuit 4, the signal processing G / A circuit 3, and the phase control of the clock sent to the panel are performed, and a slight deviation between each clock and the signal is corrected. It also outputs each timing signal required on the panel. The system microcomputer unit 10 performs various video control processing, remote controller and main body key 11 control, input signal frequency detection, and the like.

Various image control processes include bright (BRIGHTNESS) and contrast (CONTR).
AST data is signal processing G / A3, H position (POS)
ION), V position (POSITION), H amplitude (AMPLITUDE), H phase (PHASE), H area (AREA), and V area (AREA) data are transferred to timing G / A7 and controlled.

The input signal frequency is detected by the synchronization discrimination circuit 6
Then, the system microcomputer 10 discriminates the voltage value proportional to the horizontal frequency and the sync polarity information, and reads the inside of the memory from the EEPROM 12 to transfer the data corresponding to the signal.

Next, the operation of the present invention will be described with reference to FIGS. In the multi-frequency liquid crystal projector device of the present invention, it is possible to forcibly cancel the automatic screen adjustment processing by inputting the automatic screen adjustment function OFF command from the main body key / remote control unit 11. In the multi-frequency compatible liquid crystal projector device of the present embodiment, when it is determined that the input signal has been switched from the synchronization determination data sent from the synchronization determination processing unit 6 to the system microcomputer 10, the automatic screen adjustment function control information is read from the EEPROM 12. If this value is 0 (OFF), automatic screen adjustment processing is not performed. When it is 1 (ON), the automatic screen adjustment process is not performed, the signal data corresponding to the input signal is read from the EEPROM 12, and the video control process is executed.

The ON / OFF control process of the automatic screen adjustment function is performed by inputting an automatic screen adjustment function control command from the main body key / remote control unit 11 to turn the automatic screen adjustment function ON.
This is performed by writing the N / OFF information in the automatic screen adjustment function control information area of the EEPROM 12.

Next, a second embodiment of the present invention will be described.

FIG. 4 is a flowchart of the automatic screen adjustment function control process executed by the multi-frequency liquid crystal projector device according to the second embodiment of the present invention. FIG. 5 is a schematic diagram of signal data storage contents of the multi-frequency compatible liquid crystal projector device according to the second embodiment of the present invention.

The operation of the present embodiment will be described with reference to FIGS.

In the multi-frequency liquid crystal projector device of the present embodiment, the automatic screen adjustment function is controlled by changing the permissible variation range of the input signal for each signal data.

Further, it is possible to set valid / invalid of the automatic screen adjustment function control for each signal data, and when it is invalid, ON / OFF control of the automatic screen adjustment function cannot be performed. When the automatic screen adjustment function control is valid signal data, the ON / OFF information of the automatic screen adjustment function is EEPR.
It is written in the automatic screen adjustment function control information area corresponding to the signal data of the OM 12, and the automatic screen adjustment function is controlled by this value.

When the automatic screen adjustment function is ON, the allowable fluctuation range of the input signal is expanded and the automatic screen adjustment process is not executed even if the input signal changes due to noise or the like.

Next, a third embodiment of the present invention will be described.

FIG. 6 shows H, H of the third embodiment of the present invention.
It is a block diagram of a V signal input unit. In FIG. 6, the signal input terminal 13a is a signal input terminal for which the automatic screen adjustment function is valid, and the signal input terminal 13b is a signal input terminal for which the automatic screen adjustment function is invalid.

The operation of this embodiment will be described with reference to FIG. In the third embodiment of the present invention, the display signal input terminals are provided in two systems, and the input terminals of the display input signals are switched by inputting an input switching command from the main body key / remote control unit 11. The automatic screen adjustment function can be controlled only when the input terminal 13a for which the automatic screen adjustment function control is effective is selected as the display input signal.

In the first, second and third embodiments, the EEPROM is used as the digital memory, but the RAM is used.
Can also be used, and if a display input signal is fixed, a ROM (PROM), mask ROM, etc. can also be used.

In the first and second embodiments, command input from the main body key / remote control unit is used as a method of executing control of the automatic screen adjustment function.
It is also possible to control externally from an external control device connected by RS485 or RS-422.
It can also be controlled by a P switch or the like.

In the third embodiment, the signal input terminals are of two systems, but it is of course possible to provide two or more signal input terminals.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a flowchart of automatic screen adjustment processing executed by the first embodiment of the present invention.

FIG. 3 is a schematic diagram of signal data storage contents according to the first embodiment of the present invention.

FIG. 4 is a flowchart of an automatic screen adjustment function control process executed by the second embodiment of the present invention.

FIG. 5 is a schematic diagram of signal data storage contents according to the second embodiment of the present invention.

FIG. 6 is a block diagram of an H / V signal input unit according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 clamp amplification circuit 2 A / D conversion circuit 3 signal processing G / A circuit 4 D / A conversion circuit 5 drive amplification circuit 6 synchronization determination circuit 7 timing G / A circuit 8 VCO (Voltage Control Os)
9) PLL circuit (Phase Locked Loo)
p) 10 system microcomputer circuit 11 main body key / remote control unit 12 EEPROM 13a, 13b H, V signal input terminal

Claims (3)

[Claims] 1. In a multi-frequency compatible display device capable of displaying various video input signals having different specifications, a means for recognizing the synchronization frequency by counting the synchronization signal intervals of the input signals and a means for recognizing the various synchronization signal frequencies are provided. Means for storing display state information of the synchronizing signal frequency permissible range, display position and display amplitude of the display device with respect to the display signal, and means for setting and storing the control of the automatic screen adjustment function for each display state information. An input means for inputting a command for controlling the automatic screen adjustment function, and a display input when a command for controlling the automatic screen adjustment function is input by the command input means. Check whether the signal is a signal that can control the automatic screen adjustment function. If the automatic screen adjustment function can be controlled, turn on / off the automatic screen adjustment function. Storing the full information, if the automatic screen adjustment function is disabled, multi-frequency response display apparatus characterized by switching of the input signal is not used to automatically screen adjustment be detected. 2. The multi-frequency compatible display device according to claim 1, wherein a variation allowable range of a synchronizing signal frequency of a display input signal is changed as the automatic screen adjustment function control method. 3. As a means for enabling / disabling the automatic screen adjustment function control, the input terminal for the display input signal has two systems, an input terminal for which the automatic screen adjustment function control is enabled and an input terminal for which the automatic screen adjustment function control is disabled. 2. The multi-frequency compatible display device according to claim 1, wherein the command input means is the input terminal.