JP2000267061A - Liquid crystal projector and lamp unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid crystal projector and a lamp unit in which the lighting period of the lamp can be easily known and the operational load on a user is decreased. SOLUTION: The liquid crystal projector to modulate the light emitted from a lamp 3 by a liquid crystal and to project and display is provided with a lamp unit 1 equipped with the lamp 3 and a memory 5 to memorize the lighting period of the lamp 3 as detachable. The lighting time of the lamp 3 recorded in the memory 5 is visibly recognized and can not be initialized. Since the lamp unit 1 is equipped with the memory 5 to record the lighting period of the lamp 3, an user has only to check the lamp unit 1 to know the lighting time of the lamp 3, and is not required to check the memory in the liquid crystal projector as performed in a conventional device. Thus, maintenance and failure analysis is easy for manufacture, and the accurate lighting time of the lamp can be known to prevent such a danger that the lighting time of the lamp is missed when the lamp 3 is exchanged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal projector and a lamp unit which facilitate maintenance and trouble analysis of a lamp.

[0002]

2. Description of the Related Art In recent years, liquid crystal projectors have been widely used in presentations and the like because the display dots have been made finer and high-quality images can be displayed.
In this case, as criteria for the user to select a liquid crystal projector, a large number of display dots, a bright image to be displayed, and a long lamp life are important differentiating factors.

[0003] In recent years, the life of lamps has tended to be prolonged, but since the life of lamps has expired in a predetermined time, replacement and maintenance of lamps is simple, and failure analysis in the event of lamp failure is easy. It is also important.

FIG. 7 shows an example of a conventional lamp unit for a liquid crystal projector. In the lamp unit 71 for a liquid crystal projector, a lamp 73 such as a metal halide lamp is housed inside a lamp house 72.
A connector 76 for supplying power to the lamp 73 is provided on the outer wall of the lamp 73.

[0005] The connector 76 is provided with a + terminal 77 and a-terminal 78 connected to the lamp 73, and the lamp 73 is turned on by a DC power supplied from a liquid crystal projector.
When replacing the lamp 73, the lamp unit 7 must be replaced.
Each lamp unit can be replaced with a new lamp unit 71, and the user can easily replace the lamp 73.

In this case, as a replacement time of the lamp 73, a time until the brightness of the lamp 73 is reduced by half from the initial time, for example, 500 hours or 1000 hours is one standard. However, in a metal halide lamp often used in a liquid crystal projector, the time until the brightness is reduced to half may vary considerably due to manufacturing variations of the lamp 73.

[0007] On the other hand, if the use of the lamp 73 is continued after the half-life period, the probability that the lamp 73 will eventually burst increases. Although the lamp 73 is housed in the explosion-proof lamp house 72 from the viewpoint of safety, a loud noise is generated when the lamp 73 ruptures. Is displayed on-screen.

FIG. 8 is a schematic block diagram of a conventional liquid crystal projector. The liquid crystal projector 81 is supplied with a video signal from an external personal computer, a video tape recorder 39, or the like. The video signal is amplified by the video amplification circuit 35 in the control circuit 83 and supplied to the liquid crystal 41.

On the other hand, the commercial 100 V is supplied from the terminal 40 to the power supply unit 36, converted into a predetermined voltage, and supplied to the microcomputer 31, the control circuit 83 and the ballast 37. The ballast 37 generates a voltage required for lighting the lamp 73. The lamp 73 emits light from a power supply supplied from the ballast 37, and the light is modulated by the liquid crystal 41 and projected from the projection lens 23 onto a screen (not shown) or the like.

A part of the power supplied from the power supply section 36 to the control circuit 83 is supplied to a counting circuit 84 in the control circuit 83. Since the time during which the lamp 73 is lit is equal to the time during which the power supply unit 36 and the ballast 37 are operating,
The lighting time of the lamp 73 is determined by the counting circuit 84 from the power supply section 36.
Is detected by the presence or absence of power supplied to the power supply.

The counting circuit 84 counts the time during which power is supplied from the power supply section 36 as the lighting time of the lamp 73, and sends the data to the microcomputer 31. The microcomputer 31 accumulates the lighting time of the lamp 73 each time the liquid crystal projector 81 is used, and stores the total lighting time in the memory 32.

When the total lighting time of the lamp 73 has reached the above-mentioned half-life, that is, when the total lighting time has reached, for example, 500 hours, a message to that effect is displayed on the screen and the user is required to replace the lamp 73. Is urged.

[0013]

However, since the lighting time of the conventional lamp 73 is stored in the memory 32 of the microcomputer 31 built in the liquid crystal projector 81, for example, the brightness of the lamp 73 suddenly decreases. In such a case, the following inconveniences occur in maintenance.

Since the lamp 73 for the liquid crystal projector 81 is a consumable item but expensive, if the lamp 73 becomes dark before the half-life has elapsed, the user knows the lighting time of the lamp 73 in order to request compensation. There is a need. But,
In the conventional liquid crystal projector 81, the lighting time of the lamp 73 had to be read out from the memory 32 of the microcomputer 31, and the burden on the user was large.

In many cases, the user prepares a plurality of lamps 73, and when the lamp 73 becomes dark, replaces the lamp 73 with a new lamp 73 and continues to use the liquid crystal projector 81. If the user forgets to reset the memory 32 of the microcomputer 31 at the time of replacement, the lighting time of the new lamp 73 cannot be counted.

On the other hand, if the user claims that the brightness has decreased before the half-life time has elapsed and returns the lamp 73 and requests compensation therefor, the maker makes a request from the memory 32 of the liquid crystal projector 81. It is necessary to read out the lighting time of the lamp 73, which imposes a heavy burden on maintenance.
In addition, if the user resets the memory 32 improperly or the like, the accurate lighting time of the returned lamp 73 cannot be known.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal projector and a lamp unit in which the lighting time of the lamp can be easily known and the operation burden on the user can be reduced.

Another object of the present invention is to provide a liquid crystal projector and a lamp unit in which the lighting time of the lamp cannot be reset improperly and maintenance and trouble analysis on the manufacturer side are easy.

[0019]

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal projector for projecting and displaying light emitted from a lamp by modulating the light emitted from the lamp with a liquid crystal, the lamp unit having the lamp and a memory for storing the lighting time of the lamp. Is achieved by providing a liquid crystal projector that is detachably provided.

According to the present invention, since the memory for storing the lighting time of the lamp is provided in the lamp unit detachable from the liquid crystal projector, even when the user replaces and uses a plurality of lamp units, individual lamp units can be used. The lighting time of the lamp can be accurately recorded.

Further, the lamp lighting time can be known only by examining the lamp unit, and it is not necessary to examine the memory of the liquid crystal projector as in the prior art, so that maintenance and trouble analysis become easier for the manufacturer.

Further, the liquid crystal projector according to the present invention has a counter for recognizing the lighting time of the lamp stored in the memory.

According to the present invention, since the lighting time of the lamp stored in the memory can be visually recognized, for example, it is not necessary to electrically read the lighting time of the lamp from the memory of the liquid crystal projector as in the related art. The operational burden on the user can be reduced.

Further, the above object is characterized in that it has a lamp which emits light to be projected by being modulated by liquid crystal, and a memory which stores a lighting time of the lamp, and which is detachably attached to the liquid crystal projector. This is achieved by providing a lamp unit for a liquid crystal projector.

According to the present invention, since the lamp unit has a memory for storing the lighting time of the lamp, there is no fear that the lighting time of the lamp will be lost when the lamp is replaced as in the prior art, and the accuracy of the lamp is reduced. The lighting time can be known.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, such embodiments do not limit the technical scope of the present invention.

FIG. 1A is a configuration diagram of a lamp unit for a liquid crystal projector according to an embodiment of the present invention. The lamp unit 1 of the present embodiment includes an explosion-proof lamp house 2.
In addition, a lamp 3 serving as a projection light source of the liquid crystal projector and a memory 5 for counting the lighting time of the lamp 3 are incorporated. The lamp 3 uses a metal halide lamp or the like having a high emission luminance and a long life, and the memory 5 is a heat-resistant mechanical or electromagnetic type because the temperature inside the lamp house 2 becomes high. Use a device that cannot be reset.

On the upper surface of the lamp house 2, there is provided a connector 6 connected to the main body of the liquid crystal projector. The connector 6 has a lamp + terminal 9 and a lamp-terminal 10 for supplying power to the lamp 3, and a memory 5. A memory + terminal 7 and a memory-terminal 8 for supplying a drive signal are provided.

A window 4 is provided on the rear surface of the lamp house 2 so that the lighting time of the lamp 3 counted in the memory 5 can be viewed from outside the lamp house 2. Fig. 1 (2)
Indicates a case where the lamp unit 1 is viewed from the rear side, and the lighting time of the lamp 3 displayed on the counter 11 of the memory 5 can be read through the window 4 of the lamp house 2.

According to the present embodiment, since the lighting time of the lamp 3 stored in the memory 5 can be visually recognized, the user can easily know the lighting time of the lamp 3 as in the conventional case. In addition, it is not necessary to electrically read out the lighting time of the lamp 3 from the memory of the liquid crystal projector, so that the operation burden on the user can be reduced.

Further, according to the present embodiment, the lighting time of the lamp 3 stored in the memory 5 cannot be easily initialized from the outside, so that unauthorized reset of the lighting time is prevented, and the lighting time of the lamp 3 is reduced. It can be counted properly.

FIG. 2 is a schematic structural view of the liquid crystal projector according to the embodiment of the present invention. LCD projector 21
Is usually installed on a desk or the like, and projects a light beam modulated by a video signal from the projection lens 23 to display a video. A concave portion 24 for housing the lamp unit 1 is provided at a rear portion of the liquid crystal projector 21 so that a user can easily attach and detach the lamp unit 1.

When the lamp unit 1 is inserted into the recess 24, the connector 6 of the lamp unit 1 is connected to the main body side connector 22 of the liquid crystal projector 21, and the power supply for the lamp 3 and the lighting time of the lamp 3 are counted from the liquid crystal projector 21. Is supplied. Note that the lighting time of the lamp 3 can be read from the outside even when the lamp unit 1 is inserted into the liquid crystal projector 21, and the lighting time of the lamp 3 can be easily managed.

As described above, the lamp unit 1 of the present embodiment has the memory 5 for storing the lighting time of the lamp 3, so that the lamp 3 is replaced when the lamp 3 is replaced as in the prior art.
It is possible to know the exact lighting time of the lamp 3 without fear of losing the lighting time of the lamp 3.

In order to know the lighting time of the lamp 3, only the lamp unit 1 needs to be checked, and it is not necessary to check the memory of the liquid crystal projector as in the prior art.

FIG. 3 is a schematic block diagram of a liquid crystal projector according to an embodiment of the present invention. A video signal is supplied to the liquid crystal projector 21 of the present embodiment from an external personal computer, a video tape recorder 39, or the like, and the video signal is amplified by the video amplification circuit 35 of the control circuit 33 and supplied to the liquid crystal 41. .

On the other hand, the commercial 100 V is supplied from the terminal 40 to the power supply unit 36, converted into a predetermined voltage, and supplied to the microcomputer 31, the control circuit 33 and the ballast 37. The ballast 37 converts the voltage supplied from the power supply unit 36 into a voltage required for lighting the lamp 3. That is, the ballast 37 generates a high voltage of about 10 KV at the start of lighting of the lamp 3, and thereafter generates a stable DC 70V voltage. When power is supplied from the ballast 37, the lamp 3 emits light, and the light of the lamp 3 is modulated by the liquid crystal 41 and projected from the projection lens 23 onto a screen (not shown) or the like.

The + terminal 38 of the ballast 37 is connected to the L1 terminal of the counting circuit 34, the L2 terminal of the counting circuit 34 is connected to the lamp + terminal 9 of the connector 6, and the lamp-terminal 10 of the connector 6 is connected to the ballast. 37 is connected to the negative terminal 39. When the lamp 3 is turned on, the ballast 37
Since the lighting current Ia flows through the lamp 3, the lighting current Ia is monitored by the counting circuit 34 to detect the lighting time of the lamp 3.

The M1 terminal of the counting circuit 34 is connected to the memory + terminal 7 of the connector 6, and the M2 terminal of the counting circuit 34 is connected to the memory-terminal 8 of the connector 6. The counting circuit 34 outputs a current pulse Im corresponding to the time during which the lighting current Ia flows from the M1 terminal, as described later,
The memory 5 counts the lighting time of the lamp 3 based on the current pulse Im. The lighting time of the lamp 3 for each use of the liquid crystal projector 21 is sent to the microcomputer 31 and integrated, and the total lighting time of the lamp 3 is stored in the memory 3.
2 is stored.

Then, when the total lighting time of the lamp 3 reaches the above-mentioned half-life, that is, the total lighting time is, for example, 5
At 00 hours, the replacement of the lamp 3 is displayed on the screen to notify the user.

FIG. 4 shows a counting circuit 34 according to an embodiment of the present invention.
FIG. 5 is an operation timing chart of the counting circuit 34. The operation of the counting circuit 34 will be described with reference to FIGS.

As described above, the L1 terminal of the counting circuit 34 is connected to the + terminal 38 of the ballast 37,
The two terminals are connected to the lamp + terminal 9 of the connector 6. A part of the lighting current Ia of the lamp 3 is extracted by the shunt circuit 51, the surge voltage and the like are removed, and the lighting current Ia is applied to the light emitting diode 53 of the photocoupler 52. Therefore, the lighting current Ia of the lamp 3 shown in FIG.
Is detected, the lighting time T of the lamp 3 can be detected.

When the current Ib flows through the light emitting diode 53, the light emitting diode 53 emits light during that period, and the transistor 54 of the photocoupler 52 becomes conductive. Transistor 5
The collector terminal of the transistor 4 is connected to the power supply +5 V via the resistor 55, and the emitter terminal of the transistor 54 is grounded. Therefore, when the transistor 54 is turned on, the collector terminal of the transistor 54 becomes the ground potential GND.

Therefore, the signal S1 at the collector terminal of the transistor 54 has a polarity opposite to that of the lighting current Ia as shown in FIG. 5B, and the signal S2 obtained by inverting the signal S1 by the inverter 56 is shown in FIG. As shown in 3), the lighting current Ia
And a signal of the same polarity. The timer circuit 57 is an oscillator that generates a rectangular wave having a cycle t when a power supply of +5 V is applied. FIG. 5C shows the oscillation signal S3 of the timer circuit 57.
Shown in

The output signal S2 of the inverter 56 and the oscillation signal S3 of the timer circuit 57 are input to an AND circuit 58. Since the AND circuit 58 outputs the logical product of the input signals, as shown in FIG. 5 (5), the output signal S4 of the AND circuit 58 becomes the oscillation signal S3 of the timer circuit 57, and the output signal S2 of the inverter 56 becomes H The signal is extracted during the level period, that is, the lighting time T of the lamp 3. AND circuit 5
8 is input to the base terminal of the transistor 59.

The collector terminal of the transistor 59 is connected to the M2 terminal of the counting circuit 34, and the emitter terminal of the transistor 59 is grounded. The M1 terminal of the counting circuit 34 is connected to the power supply + 5V. And the M1 terminal and M
The memory 5 of the lamp unit 1 is connected between the two terminals.

Therefore, while the output signal S4 of the AND circuit 58 is at the H level, the transistor 59 is turned on and the memory 5 is turned on.
A current pulse Im flows through. The current pulse Im is shown in FIG.
As shown in (6), the timing is the same as that of the output signal S4 of the AND circuit 58. In the case of FIG. 5, six current pulses Im having a period t are output. One cycle t of the timer circuit 57
Can be set arbitrarily. For example, when t = 0.01H, the lighting time T of the lamp 3 is 6 × t = 0.
06H.

FIG. 6 is a display example of an electromagnetic memory used in the liquid crystal projector according to the embodiment of the present invention. The electromagnetic memory 5 is a kind of integrating counter, and when a pulse current Im is applied to a coil of an internal electromagnet, the electromagnet operates and counts one per pulse.

FIG. 6A shows a 6-digit electromagnetic memory 5.
The cycle t of the pulse current Im is set to t = 0.
When 01H is set, the least significant digit is counted by 1 every t = 0.01H. Therefore, in the case of FIG. 6A, the digit of 0.01H, the digit of 0.1H, the digit of 1H, and the digit of 10H are sequentially arranged from the least significant digit.
Digit, 100H digit, 1000H digit, up to 99
It can count up to 99.99H. FIG. 6B shows a case where six pulse currents Im are input as shown in FIG. 5, and 0.06H is displayed.

As described above, according to the present embodiment, the lighting time of the lamp 3 stored in the memory 5 can be visually recognized, so that the user can easily know the lighting time of the lamp 3. The operational burden on the user can be reduced.

Further, according to the present embodiment, since the lighting time of the lamp 3 stored in the memory 5 cannot be easily initialized from the outside, illegal resetting of the lighting time is prevented, and the lighting time of the lamp 3 is reduced. It can be counted properly.

[0052]

As described above, since the lamp unit of the present invention has a memory for storing the lighting time of the lamp, the lighting time of the lamp can be determined by examining only the lamp unit. Since there is no need to check the memory of the liquid crystal projector, maintenance and failure analysis become easier for the manufacturer.

Further, there is no fear that the lighting time of the lamp will be lost when the lamp is replaced as in the prior art, and the accurate lighting time of the lamp can be known.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a lamp for a liquid crystal projector according to an embodiment of the present invention.

FIG. 2 is a structural diagram of a liquid crystal projector according to an embodiment of the present invention.

FIG. 3 is a block diagram of the liquid crystal projector according to the embodiment of the present invention.

FIG. 4 is a circuit diagram of a counting circuit according to the embodiment of the present invention.

FIG. 5 is an operation timing chart of the counting circuit according to the embodiment of the present invention.

FIG. 6 is a display example of the electromagnetic memory according to the embodiment of the present invention.

FIG. 7 is a configuration diagram of a conventional lamp for a liquid crystal projector.

FIG. 8 is a block diagram of a conventional liquid crystal projector.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lamp unit 2 Lamp house 3 Lamp 4 Window 5 Memory 6 Connector 7 Memory + Terminal 8 Memory−Terminal 9 Lamp + Terminal 10 Lamp−Terminal 31 Microcomputer 32 Memory 33 Control circuit 34 Counting circuit 36 Power supply section 37 Stabilizer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) G09F 9/00 360 G02F 1/1335 530 F term (reference) 2H088 EA12 HA07 HA28 MA20 2H091 FA41Z FD11 GA12 LA09 MA07 2H093 NC56 ND60 NE06 NG02 5G435 AA19 BB17 DD04 DD09 EE02 EE18 EE30 GG28

Claims (4)

[Claims] 1. A liquid crystal projector for modulating light emitted from a lamp with liquid crystal and projecting and displaying the light, wherein a lamp unit having the lamp and a memory for storing a lighting time of the lamp is detachably provided. Characteristic liquid crystal projector. 2. The liquid crystal projector according to claim 1, further comprising a counter for recognizing a lighting time of the lamp stored in the memory. 3. A lamp for a liquid crystal projector, comprising: a lamp for emitting light modulated and projected by liquid crystal; and a memory for storing a lighting time of the lamp, the lamp being detachably attached to the liquid crystal projector. unit. 4. The lamp unit for a liquid crystal projector according to claim 3, further comprising a counter for recognizing a lighting time of the lamp stored in the memory.