CN100428053C - Projector and method for judging residual service life of projector lamp - Google Patents

Abstract

A device and method for judging the remaining service life of a projection lamp of a projector, first measuring the lamp voltage between a pair of filament electrodes of a projection lamp; converting the lamp voltage into a digital value; and calculating the residual service life of the projection lamp according to the relation between the lamp tube voltage and the residual service life of the lamp.

Description

Projector and method for judging remaining service life of projector lamp

technical field

The present invention relates to a projector, in particular to a projector device capable of detecting the remaining service life of a projection lamp, and a detection method thereof.

Background technique

The projector optically processes the light beam emitted by a light source to form an optical image, and uses a projection lens (projection lens) to enlarge and project the optical image. This type of projector is widely used in interviews, academic conferences and It will be used as a display at the expo. The light source of the projector traditionally uses a projection lamp, such as a metal halide lamp or a helium lamp.

In the case of safety considerations, or preset the safe use time of the projection lamp, when the projection lamp is installed and used, it will emit a fairly stable light for hundreds of hours, such as 900 hours, but if the projection lamp is used more than itself When the service life is reached, the projection lamp will burn out, and the projection lamp may explode, causing danger to users.

For this reason, in traditional and commercially available projectors, a timer is used to accumulate the used time of the projection lamp, and when the accumulated time reaches the predetermined safe use time, the user is notified to replace the projection lamp tube. However, even between the same type of projection lamps, there will be a difference in service life (to1erance), which means that for the same type of projection lamps, some lamps may not burn out immediately even if they are used beyond the predetermined service life. It is also related to the habit of use. If you use a high-brightness projector for a long time, its service life will be shorter, and if you use a low-brightness projector for a long time, its service life will be longer. Lamps, regardless of the differences in the use of each lamp and the user's habits, will cause the lamp to be replaced after hundreds of hours of use, resulting in unnecessary waste.

In view of the fact that the projection lamps installed in the projectors on the market, such as OSRAM, PHILIP or Ushio and other brands of lamps, all have the same characteristics, that is, if the filament electrodes of the projection lamps use the same voltage, the brightness of the lamp will increase with use. Time increases and becomes darker. In order to maintain the same brightness of the projection lamp, the voltage between the filament electrodes of the projection lamp needs to be increased. Therefore, when the projection lamp is in normal use, the voltage between the filament electrodes of the projection lamp,

Will increase with use time. Therefore, the present invention uses this characteristic as a criterion for judging the life of the lamp, so as to inform the user to prepare for replacing the lamp.

Contents of the invention

In view of this, the primary purpose of the present invention is to provide a method for judging the remaining service life of the projection lamp of the projector. remaining useful life.

According to the stated purpose, the present invention provides a projector, including an image projection device, which is provided with a projection lamp and has a pair of filament electrodes; a detection unit for detecting the voltage between the pair of filament electrodes; an analog-digital a converter for converting the voltage into a digital value; and a control unit for calculating the remaining life of the projection lamp by comparing the digital value with a comparison table recording the relationship between the remaining life of the lamp and the voltage between the filament electrodes of the lamp. service life.

According to the stated purpose, the present invention also provides a method for judging the remaining service life of a projection lamp of a projector, comprising measuring the voltage between a pair of filament electrodes of a projection lamp; converting the voltage into a digital value; and converting the digital value The remaining service life of the projection lamp is calculated by comparing with a comparison table that records the relationship between the remaining life of the lamp and the voltage between the filament electrodes of the lamp.

In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, a preferred embodiment is specifically cited below, together with the accompanying drawings, and the detailed description is as follows:

Description of drawings

FIG. 1 is a schematic diagram of a projector capable of judging the remaining lifetime of a projection lamp according to the present invention.

Fig. 2 is a graph showing the relationship between the lamp tube voltage and the remaining life of the lamp.

Figure 3 is a graph illustrating the relationship between lamp operating time and lamp tube voltage.

FIG. 4 is a flowchart of a method for judging the remaining service life of a projector lamp according to the present invention.

Symbol Description

10: Image projection device; 12: Projection lamp;

13: ballast; 14: detection unit;

16: Analog/digital converter; 18: Control unit;

20: storage unit; 22: timer;

121, 122: filament electrode; 100: projector;

Va: Lamp voltage.

Detailed ways

As shown in FIG. 1 , it is a projector 100 of the present invention capable of judging the remaining life of a projection lamp. The projector 100 includes an image projection device 10, is provided with a projection lamp 12, has a pair of filament electrodes 121, 122; a detection unit 14 is used to detect the voltage between the pair of filament electrodes 121, 122, generally called a lamp tube voltage; an analog-to-digital converter 16 for converting the voltage into a digital value; and a control unit 18 for calculating the remaining service life of the projection lamp 12 by comparing the digital value with a look-up table.

Wherein the image projection device 10 utilizes the light beam emitted by the projection lamp 12 to form an optical image, and utilizes a projection lens (projection lens) to amplify and project the optical image.

In addition, the projection lamp 12 can be a metal halide lamp or a helium lamp, etc. . . . At the same time, when the projection lamp 12 is installed and used, it will emit fairly stable light for hundreds of hours, for example, 900-1100 hours, within the range of safe use time. Furthermore, this type of projection lamp 12 has a characteristic, which is the voltage Va of the lamp tube between the filament electrodes 121 and 122 of the projection lamp 12. To maintain the high brightness projected by the projection lamp, the voltage Va will increase as the usage time increases. , indicating that the lamp voltage Va between the filament electrodes is relatively low when the projection lamp 12 is new, for example, 60-85 volts, and as the number of hours of use increases, the lamp voltage Va will gradually increase, to about 115-120 volts Keep the lights at the same brightness. Therefore, in the present invention, this characteristic is used as a criterion for judging the life of the lamp, so as to inform the user to prepare for replacing the lamp. As shown in FIG. 2 , it is a graph showing the relationship between the voltage of the lamp tube and the remaining life of the lamp.

The detection unit 14 is connected to the two voltage input terminals of the filament electrodes 121 and 122 , such as a voltage sensor, to detect the lamp voltage Va applied between the filament electrodes 121 and 122 . In addition, the projector 100 of the present invention also includes a ballast 13, which is connected to both ends of the filament electrodes 121, 122 of the projection lamp 12, so as to ease the change of the current in the projection lamp 12 and help the start-up of the projection lamp 12. , and a timer 22 for recording the time that the projection lamp 12 has been used.

An analog-digital converter 16 (analog-digital converter, ADC) can convert an analog voltage or current signal into an equivalent digital signal for processing by a digital circuit such as a microprocessor. In the present invention, the analog-to-digital converter 16 is used to convert the lamp voltage Va (analog voltage) into a digital value.

The control unit 18, for example, is a microcontroller (micro controller unit), connected to the analog-to-digital converter 16, in order to calculate the remaining power of the projection lamp 12 by comparing the digital value with a look-up table. Service life (lamp lift time). At the same time, the projector 10 of the present invention may also include a storage unit 20 for storing the comparison table. The comparison table records the relationship between the lamp voltage between the filament electrodes and the remaining life of the lamp, and is pre-stored in the storage unit. 20 in.

Taking OSRAM AC's 130-watt projection lamp as an example, after many tests, it is known that most of its lifespan exceeds 1000 hours, and some of them can reach 1500 hours, but most of them are placed between the filament electrodes 121 and 122. When the voltage Va is around 110 volts, it is damaged, as shown in FIG. 3 .

Therefore, in this embodiment, 110 volts is used as a critical voltage value. When the lamp voltage Va is greater than 110 volts, the lamp should be replaced immediately to ensure that users use the projector within a safe range. Va is 105 volts, and if the lamp tube voltage Va increases by 1 volt after about 3.3 hours of use, it can be calculated that the projection lamp 12 has about 16 hours of remaining service life. For example, it can be displayed in the projected data to inform the user of the remaining service life of the projection lamp 12 , and the detection action is usually performed when the projector 10 is turned on.

If the detection unit 14 detects that the lamp voltage Va exceeds 110 volts or is close to 110 volts, or when the remaining service life is less than a predetermined number of hours, such as 5 hours, then output a warning signal, such as displayed on the projected In the optical image, to inform the user that the projection lamp 12 must be replaced immediately. If the user does not replace the projection lamp immediately, the control unit 18 will start the timer 22 at the same time after the projector is turned on, and use the timer 22 for a predetermined time, for example, automatically shut down the projector after 5 minutes, so as to prevent the lamp voltage from continuing to increase and cause damage. cause danger.

As shown in FIG. 4 , it is a flow chart of the method for judging the remaining service life of the projector lamp of the present invention.

First in step 11, when the projector 100 is turned on, the detection unit 14 will measure the lamp voltage Va applied between the filament electrodes 121, 122, or first measure the time that the projection lamp 12 of the projector has been used, if When the projection lamp 12 of the projector has been used for a predetermined number of hours, the next step is performed.

Then in step 13 , an analog-to-digital converter 16 is used to convert the measured lamp voltage Va into a digital value.

Finally, in step 15, use the control unit 18 to calculate the remaining service life of the projection lamp 12 according to the digital value and a comparison table that records the relationship between the lamp voltage between the filament electrodes and the remaining service life of the lamp, and at the same time, Displaying the remaining service life of the projection lamp, for example, can be simultaneously displayed in the image projected by the projector. In addition, when the remaining service life of the projection lamp 12 is less than a predetermined number of hours, the control unit outputs a warning signal to inform the user to replace the projection lamp.

Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention, and any person skilled in the art can make changes and improvements without departing from the spirit and scope of the present invention. Therefore, the present invention Scope of Protection The scope defined by the proposed claims shall prevail.

Claims (9)

1. a projector has the function of the residual life of differentiating projecting lamp, comprising:

One projecting lamp, this projecting lamp has a pair of filament electrode;

One detecting unit is in order to detect this to the magnitude of voltage between filament electrode;

One analogue-to-digital converters are in order to convert this magnitude of voltage to a digital value; And

One control module receives this digital value, and utilizes comparison list, by with the table of comparisons of voltage relationship between the filament electrode of the residual life of this digital value and a recording lamp and lamp relatively, calculates the remaining life of this projecting lamp.

2. projector as claimed in claim 1 also comprises a storage unit, in order to store this table of comparisons.

3. projector as claimed in claim 1, wherein this control module is exported a caution signal when when this remaining life is lower than a default value.

4. projector as claimed in claim 3 also comprises a timer, and this timer picks up counting a schedule time after projector starts, and service time of this projector was defined in this schedule time.

5. projector as claimed in claim 1, wherein for to keep the certain brightness of this projecting lamp, this projecting lamp has the characteristic that the voltage between filament electrode increased along with service time.

6. method of differentiating the remaining life of projector's lamp comprises:

Measure the voltage between a pair of filament electrode of projector's lamp;

Change this voltage and become a digital value; And

With the table of comparisons of voltage relationship between the filament electrode of the residual life of this digital value and a recording lamp and lamp relatively, to calculate the remaining life of this projector's lamp.

7. the method for differentiating the remaining life of projector's lamp as claimed in claim 6 also comprises a step:

The remaining life that shows this projector's lamp.

8. the method for differentiating the remaining life of projector's lamp as claimed in claim 6 also comprises when the remaining life of this projector's lamp is less than a predetermined value, exports a caution signal.

9. the method for the remaining life of differentiation as claimed in claim 8 projector lamp also is included in projector's one schedule time of timing when starting, with projector use time qualified in this schedule time.

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