JP2012215755A - Light source device and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cause an output level of light as a specific color to be hardly reduced while suppressing a change in color balance of the specific color even when deterioration of a part of light sources is accelerated when light of the specific color is output by combining the light sources of a plurality of colors.SOLUTION: A light source device comprises: a first light source section that has a first light emitting body and outputs first light; a second light source section that has a second light emitting body and outputs second light; a light guiding section for guiding the first light and the second light to a light valve that modulates light; and a supplying section for supplying electric power to the first light emitting body and the second light emitting body. The electric power supplied thereto is set such that: a reduction rate of an output level of the second light in a case where electric power of a specific value is continuously supplied to the second light emitting body is greater than a reduction rate of an output level of the first light in a case where the electric power of the specific value is continuously supplied to the first light emitting body; and electric power supplied to the second light emitting body by the supplying section is less than electric power supplied to the first light emitting body thereby.

Description

  The present invention relates to a technology for controlling a light source used in a projector or the like.

There is a projector that generates a reduced image using a light valve that modulates light, such as a liquid crystal panel, and enlarges and projects the reduced image using an optical system. In recent years, light sources of projectors have been developed with light emitting diodes (LEDs) and LDs (LDs) in order to reduce the size and power consumption.
A solid state light source such as a laser diode may be used. Since a solid light source cannot output light in a wide wavelength band, a combination of a plurality of types of solid light sources that output light of different colors realizes output of white light. The solid light source deteriorates due to a decrease in the light output level depending on the light output time. However, depending on the type of the solid light source, the reduction rate of the light output may be different from other types.

In addition, in order to output different colors, the light from the solid light source itself may not be used, but the fluorescent light emitted from the fluorescent material may be used by irradiating the light from the solid light source. In general, the conversion efficiency to fluorescence in the phosphor increases as the output level of the irradiated light decreases. Therefore, even if the deterioration of all the solid light sources progresses in the same way, the decrease in the output level of the fluorescence from the phosphor is smaller than the decrease in the output level of the light from the solid light source.
When the reduction rate of the light output for each color is different as described above, the ratio of the light output level between the colors changes, and the white balance is lost. As a technique for maintaining white balance, Patent Document 1 discloses that the output level of light from a solid light source with little deterioration is reduced according to the output level of light from a solid light source with much deterioration. Yes.

Japanese Patent Application Laid-Open No. 2004-279943

In the technique disclosed in Patent Document 1, while white balance can be maintained, the output level of light from a solid light source with little deterioration is reduced, so that white light becomes dark as the solid light source deteriorates. It was something to go.
The present invention has been made in view of the above-described circumstances, and one of its purposes is to output light of a specific color by combining light sources of a plurality of colors, even if some of the light sources deteriorate quickly. It is to make it difficult to reduce the output level of light as a specific color while suppressing a change in the color balance of the specific color.

In order to solve the above-described problem, the present invention includes a first light source unit that has a first light emitter that outputs light when power is supplied, and that outputs first light using the first light emitter, A second light source that has a second light emitter that outputs light when power is supplied and outputs second light using the second light emitter, and a light valve that modulates light, A light guide unit that guides one light and the second light, and a supply unit that supplies power to the first light emitter and the second light emitter, and a specific value of power is supplied to the second light emitter. The decrease rate of the output level of the second light when it is continuously supplied is the first level.
The power supplied to the second light emitter by the supply unit is larger than the reduction rate of the output level of the first light when the specific value of power is continuously supplied to the light emitter, Provided is a light source device that is set to be less than the power supplied to the first light emitter.
According to this light source device, the power supplied to the light emitter of the light source having a large reduction rate of the light output level is less than that of the other light source, thereby suppressing the reduction rate of the light output level. It is possible to make it difficult to lower the output level of the light as the specific color while suppressing the change in the color balance of the specific color combining the light from the light.

In another preferred embodiment, the first light source unit emits fluorescence as the first light when irradiated with light from the first light emitter, and conversion efficiency to fluorescence is reduced when the amount of excitation light decreases. It has the characteristic that it has the fluorescent substance which becomes high.
According to this light source device, it is difficult to reduce the output level of light as a specific color by utilizing the effect of reducing the reduction rate of the output level of light that occurs when a phosphor is used for some light sources. Can do.

In another preferred embodiment, a detection unit that detects a first output level of the first light and a second output level of the second light, and the supply unit are controlled to be detected by the detection unit. And a power control unit configured to supply power to the second light emitter so that the relationship between the first output level and the second output level is a predetermined setting relationship. .
According to this light source device, even when the rate of decrease in the output level of light from the light emitter varies, it is difficult to reduce the output level of the light as the specific color while suppressing the change in the color balance of the specific color. can do.

Moreover, in another preferable aspect, when the power supplied to the second light emitter for setting the relationship to the set relationship exceeds a predetermined threshold,
Instead of controlling the power supplied to the second light emitter, the power supplied to the first light emitter is reduced.
According to this light source device, it is possible to increase the initial value of the output level of light as a specific color by setting the power supplied to the first light emitter as an upper limit as an initial state.

In another preferable aspect, the power control unit sets a predetermined threshold value for the power supplied to the first light emitter or the second light emitter for making the relationship the setting relationship. When it is lower, the supply of electric power from the supply unit is stopped.
According to this light source device, when the output level of light from one of the light emitters becomes too low, it is possible to stop the light output as an unexpected situation has occurred.

In another preferred aspect, the power control unit controls the power supplied from the supply unit by controlling the value of the current supplied along with the supply of the power or the duty ratio. To do.
According to this light source device, the configuration for controlling the power supplied to the light emitter can be simplified.

In another preferred embodiment, the wavelength included in the first light includes a wavelength having higher relative visibility than the wavelength included in the second light.
According to this light source device, it is possible to suppress the change in the color balance of the specific color efficiently by suppressing the influence on the vision due to the decrease in the light output level.

In another preferable aspect, when the power of a specific value is continuously supplied to the first light emitter, the reduction rate of the output level of the light output from the first light emitter, and the second light emitter When the power of the specific value continues to be supplied, the reduction rate of the output level of the light output from the second light emitter is substantially the same.
According to this light source device, the manufacturing cost can be reduced. Moreover, the setting of the electric power supplied to each can be made easy.

According to another aspect of the invention, there is provided a projector comprising: the light source device described above; the light valve; and a modulation control unit that controls light modulation contents in the light valve in accordance with an input video signal. I will provide a.
According to this projector, it is possible to make it difficult to lower the light output level while suppressing a change in the color balance of the projected image.

It is a top view which shows the structure of the projector in 1st Embodiment. It is a figure explaining the characteristic of fluorescent substance. It is a figure explaining the difference in the fall rate of the output level of excitation light and fluorescence. It is a figure explaining the difference by the power supply of the fall rate of the output level of B light. It is a figure explaining the functional structure of the projector in 1st Embodiment. It is a top view which shows the structure of the projector in 2nd Embodiment. It is a figure explaining the function structure of the projector in 2nd Embodiment. It is a flowchart explaining the electric power control process in 2nd Embodiment.

<First Embodiment>
[Configuration of Projector 2000]
FIG. 1 is a plan view showing the configuration of the projector 2000 according to the first embodiment. The projector 2000 includes a light source device having a first light source unit 210, a second light source unit 220, and a light guide unit 230, a dichroic prism 240, a projection lens 250, a display panel 100R,
100G and 100B.

The first light source unit 210 includes an excitation LD array light source 211 and a phosphor 212. L for excitation
In the D array light source 211, first light emitters 2110 (see FIG. 5), which are excitation LDs that output blue light when power is supplied, are arranged in a plurality of arrays, and a plurality of first light emitters 2110 are arranged.
It is a light source that outputs light from all together.
The phosphor 212 is irradiated with the light output from the excitation LD array light source 211 collected by the condenser lens 213. The phosphor 212 converts the irradiated light (excitation light) into fluorescent light having a wavelength distribution that is generally yellow, and outputs the fluorescence. That is, the phosphor 212 functions like a point light source that outputs fluorescence from a condensed region. The fluorescence output from the phosphor 212 is collimated by the collimating lens 214. As a result, the first light source unit 210 has the first light emitter 21.
The light from 10 is converted into fluorescence, and the converted fluorescence is output as first light.

The second light source unit 220 includes a B (blue) light LD array light source 221 and a diffusion plate 222.
The B light LD array light source 221 is a second B light LD that outputs light when power is supplied.
A light source 2210 (see FIG. 5) is a light source in which a plurality of light emitters 2210 (see FIG. 5) are arranged in an array and the light from the plurality of second light emitters 2210 is output collectively. In this example, the second light emitter 2210 is the same LD as the first light emitter 2110 (the LD whose output wavelength and output level decrease rate are substantially the same).
) And outputs blue light.
The diffusion plate 222 functions like a point light source by diffusing the light output from the B light LD array light source 221 by being condensed by the condenser lens 223 and diffusing the light from the condensed region. The light diffused in the diffusion plate 222 is collimated by the collimating lens 224. Thus, the second light source unit 220 outputs the second light using the light from the second light emitter 2210.

The light guide unit 230 combines the first light output from the first light source unit 210 and the second light output from the second light source unit 220 to generate R (red), G (green), and B (blue). ) Are separated into the three primary colors and led to the display panels 100R, 100G and 100B, respectively.
Specifically, the first light and the second light are combined by the dichroic mirror 2301C. The combined light passes through the first multi-lens 2303, the second multi-lens 2304, the polarization conversion element 2305, and the superimposing lens 2306, and two dichroic mirrors 2301.
The three primary colors R (red), G (green), and B (blue) are separated by S and three mirrors 2302. The lights separated into the three primary colors are guided to the display panels 100R, 100G, and 100B corresponding to the primary colors through the condenser lens 2308, respectively. B light is R light, G light
Compared with light, in order to prevent loss due to a long optical path, the light is guided through a relay lens system using three lenses 2307 including a relay lens.

The display panels 100R, 100G, and 100B are light valves such as a liquid crystal panel that modulates light, and are driven according to video signals corresponding to the colors R, G, and B, as described later. Reduced images are formed. Display panel 100R, 100G
, 100B respectively, the reduced images, that is, modulated light, enter the dichroic prism 240 from three directions. In the dichroic prism 240, the R light and the B light are reflected at 90 degrees, while the G light travels straight. Accordingly, after the images of the respective colors are combined, a color image is projected onto the screen 3000 by the projection lens 250.
The light valve may not be a transmissive liquid crystal panel such as the display panels 100R, 100G, and 100B. For example, a reflective liquid crystal panel may be used, or a DMD (Digital Micromirror) other than the liquid crystal panel may be used. Device) or the like may be used.

[Characteristics of phosphor 212]
FIG. 2 is a diagram for explaining the characteristics of the phosphor 212. As described above, the phosphor 212 is
The excitation light is converted into fluorescence and output. The lower the amount of excitation light, the higher the conversion efficiency. FIG. 2 shows the characteristics of the conversion efficiency of the phosphor 212 in this example, the horizontal axis indicates the excitation light amount ratio with respect to a specific excitation light amount, and the vertical axis indicates the conversion efficiency. As shown in FIG. 2, the phosphor 212 has a conversion efficiency Y1 at a specific excitation light quantity, and when the excitation light quantity ratio becomes 50%, the conversion efficiency increases to Y2 and becomes 1.2 times.

FIG. 3 is a diagram for explaining the difference in output level reduction rate between excitation light and fluorescence. In detail,
Changes in the output level of excitation light from the LD array light source 211 for excitation when a specific value of power is continuously supplied to each of the plurality of first light emitters 2110, and fluorescence output from the phosphor 212, that is, The change of the output level of the 1st light is shown. In FIG. 3, the horizontal axis represents the elapsed time since the start of power supply, and the vertical axis represents the light output level L immediately after the start of power supply.
The ratio of the output level L (t) at the elapsed time t with respect to (0) is shown.
As shown in FIG. 3, at the elapsed time t1 when the output level of the excitation light is halved to 50%,
Since the conversion efficiency of the phosphor 212 is increased by 1.2 times due to the decrease in the output level of the excitation light, the output level of the fluorescence is still maintained at 60%.

[Characteristics of Second Light Emitter 2210]
FIG. 4 is a diagram for explaining a difference in the reduction rate of the output level of the B light depending on the supplied power. Specifically, the B light from the LD array light source 221 for the B light, that is, the second light when the power of the specific value P ₀ is continuously supplied to each of the plurality of second light emitters 2210, that is, the second light. It shows a change in the output level and a change in the output level of the B light when the power of 95% of P ₀ is continuously supplied. The horizontal and vertical axes in FIG. 4 are the same as in FIG.
As shown in FIG. 4, the second light emitter 2210 in this example, by reducing the power to 95% of P _0, the elapsed time t1, to maintain the output level of the second light 60% it can.
In general, it is known that the LD is greatly affected by the junction temperature during driving. When used in the same housing such as a projector, there is no significant difference in cooling conditions depending on the location where the LD is installed, so the supplied power is a major factor affecting the junction temperature. Under such circumstances, a phenomenon as shown in FIG. 4 occurs.

As described above, when the same power P ₀ is continuously supplied to the first light emitter 2110 and the second light emitter 2210, the reduction rate of the output level of the second light is lower than the reduction rate of the output level of the first light. However, by reducing the power supplied to the second light emitter 2210, these reduction rates can be adjusted to be approximately the same.
Here, when the output level of light from the second light emitter 2210 is supplied as 95% of the electric power P ₀ , the output level is lower than that when the electric power P ₀ is supplied. By increasing the number of second light emitters 2210 in 221, it is possible to compensate for the decrease in output level.

[Function configuration]
FIG. 5 is a diagram illustrating the functional configuration of the projector 2000 according to the first embodiment. The projector 2000 includes a modulation control unit 11, a power control unit 12, and a supply unit 13 that supplies power to the first light emitter 2110 and the second light emitter 2210. The modulation control unit 11 has R, G
, B video signals corresponding to the respective colors are input, and the drive circuit 10R according to the input video signals.
By controlling 10G and 10B, reduced images corresponding to the respective colors are formed on the display panels 100R, 100G, and 100B.

The supply unit 13 includes an excitation LD drive unit 131 that supplies power to each of the first light emitters 2110,
And a B-light LD driving unit 132 that supplies power to each of the second light emitters 2210. The power control unit 12 controls the magnitude of power supplied to the excitation LD drive unit 131 and the B light LD drive unit 132 (hereinafter referred to as the supply unit 13 if they are not distinguished from each other). In this example, the power controller 12 includes the first light emitter 2 in the excitation LD driver 131.
Control is performed so that power of the specific value P ₀ is supplied to each of 110. On the other hand, the power control unit 12 controls the B light LD driving unit 132 to supply 95% of the specific value P _{0 to} each of the second light emitters 2210. The control to 95% may be realized by setting the current value to 95%, or the current value may be realized by setting the duty ratio to 95%. Note that the resistance value of the LD may increase as power is continuously supplied. In this case, unless the current value at the time of current supply is changed, the supplied power increases.

The power control unit 12 also controls the start and stop of power supply from the supply unit 13. For example, the power control unit 12 starts supplying power to the supply unit 13 when a video signal is input to the modulation control unit 11, and stops supplying power when input of the video signal is stopped. The start / stop control may be performed in conjunction with an instruction when a user inputs a start / stop instruction by operating an operation unit (not shown).

The number of first light emitters 2110 included in the excitation LD array light source 211 and the number of second light emitters 2210 included in the B light LD array light source 221 are output in a state where the supplied power is set as described above. When the first light and the second light are combined, the white balance is determined to be in a predetermined state. For example, if the conversion efficiency in the phosphor 212 and the transmittance of light diffused by the diffusion plate 222 are the same, the number of the first light emitters 2110 is 95% of the number of the second light emitters 2210. It only has to be decided to be.
Note that the conversion efficiency of the phosphor 212 is 95 of the transmittance of light diffused by the diffusion plate 222.
%, The number of first light emitters 2110 and the number of second light emitters 2210 may be the same. In this case, the first light emitter 211 constituting the excitation LD array light source 211.
The number of 0 and the number of second light emitters 2210 constituting the array light source 221 for B light may be singular instead of plural.

Thus, the projector 2000 according to the first embodiment of the present invention makes the power supplied to each of the plurality of second light emitters 2210 less than the power supplied to each of the plurality of first light emitters 2110. Thus, the reduction rate of the output level of the first light and the reduction rate of the output level of the second light can be brought close to each other, and moreover, the power can be reduced by appropriately determining the same level. You can also. That is, white balance can be maintained even if the light source is deteriorated. Conventionally, since the white balance is maintained in accordance with the light source having a large reduction rate of the light output level, the light output level is reduced to 50% at the elapsed time t1, but the first embodiment of the present invention. In the projector 2000, 60
%, And the lifetime can be extended while maintaining the white balance.

Second Embodiment
In the configuration of the projector 2000 in the first embodiment, the projector 2000A in the second embodiment further adjusts the power supplied to the first light emitter 2110 and the second light emitter 2210 to obtain a more stable white balance. For having a configuration. Hereinafter, the configuration of the projector 2000A will be described.

[Configuration of Projector 2000A]
FIG. 6 is a plan view showing a configuration of a projector 2000A according to the second embodiment.
In addition to the projector 2000 in the first embodiment, the projector 2000A
A detection unit 260 is included. Among the configurations of the projector 2000A, the projector 200
Components having the same reference numerals as 0 have the same functions as the configuration of the projector 2000, and thus description thereof is omitted.
The detection unit 260 is an RGB color sensor, and the first light and the second light are combined and arranged in the vicinity of the optical path of the combined light that becomes white light, and the R light, G light, and B light of the combined light are combined. An output level is detected, and a detection signal indicating the detected output level of each color light is output. In this example,
The detector 260 is installed between the dichroic mirror 2301C and the first multi-lens 2303, and is configured to receive a part of the combined light.

FIG. 7 is a diagram illustrating a functional configuration of the projector 2000A according to the second embodiment. The power control unit 12 in the first embodiment is controlled to supply predetermined power from the supply unit 13, but the power control unit 12 </ b> A in the second embodiment is a detection output from the detection unit 260. The power supplied from the supply unit 13 is controlled according to the signal.
The power control unit 12A starts the power control process at a predetermined timing, for example, every predetermined period. The power control process is a process for controlling the power supplied to the second light emitter 2210 in preference to the control of the power supplied to the first light emitter 2110. Specifically, the power control process has the processing contents shown in FIG.

In this example, power control is performed by controlling the magnitude of current supplied to the first light emitter 2110 and the second light emitter 2210. The initial value is the first
As shown in the embodiment, each of the first light emitters 2110 has a current I0 (
For example, it is assumed that the rated current of the first light emitter 2110 alone is supplied, and 95% of the current I0 is supplied to each of the second light emitters 2210. In the power control process,
Control for increasing the current supplied to each of the first light emitters 2110 from the current I0 determined as the initial value is not performed. Further, the upper limit value of the current supplied to each of the second light emitters 2210 is determined as the current I0. On the other hand, the lower limit value of the current supplied to each of the first light emitters 2110 and the lower limit value of the current supplied to each of the second light emitters 2210 are both current IL.
It is decided as.

FIG. 8 is a flowchart for explaining power control processing in the second embodiment. When starting the power control process, the power control unit 12A acquires a detection signal from the detection unit 260 (step S110). The power control unit 12A analyzes the acquired detection signal and calculates a color ratio indicating a ratio between the output level of the first light and the output level of the second light (step S120). The power control unit 12A determines whether or not the calculated color ratio is within a predetermined allowable value (step S130). The allowable value is determined according to a predetermined white balance. In this example, the allowable value is set as a range of the ratio of the color ratio, specifically, the ratio of the output level of the second light to the output level of the first light. As long as the allowable range is determined as a setting relationship with respect to the relationship between the output level of the first light and the output level of the second light for white balance, it may be determined in any manner.

The power control unit 12A determines that the calculated color ratio is within the allowable value (step S130; Y
es), the power control process ends. On the other hand, when the color ratio is not within the allowable value (step S130; No), the ratio of the output level of the second light (B light) is low (step S21).
0; Yes), the power control unit 12A determines that the current supplied to the second light emitter 2210 (hereinafter,
(Referred to as an LD current for B light) by a certain value Iu. However, the power control unit 1
2A, when the LD light current for B light is increased by a constant value Iu, if the current I0 of the upper limit value is not exceeded, that is, if the upper limit is not reached (step S220; No), The value is increased by a constant value Iu (step S230), and the process returns to step S110.

On the other hand, if the LD current for B light is increased by a certain value Ic and exceeds the upper limit current I0, that is, if the upper limit is reached (step S220; Yes), the power control unit 12A includes the first light emitter. The current supplied to 2110 (hereinafter referred to as the excitation LD current) is a constant value Id1
Only process to reduce. However, the power control unit 12A sets the excitation LD current to a constant value Id.
If it is decreased by 1, if it does not fall below the lower limit current IL, that is, if the lower limit is not reached (step S240; No), the excitation LD current is decreased by a constant value Id1 (
Step S250) and the process returns to Step S110. When the excitation LD current is decreased by a certain value Id, when the current falls below the lower limit current IL, that is, when the lower limit is reached (step S240; Yes), the power control unit 12A supplies power from the supply unit 13 Stop (
Step S260), the power control process is terminated.

On the other hand, when the color ratio is not within the allowable value (step S130; No) and the ratio of the output level of the second light (B light) is high (step S210; No), the power control unit 12A A process of reducing the optical LD current by a constant value Id2 (may be the same as Id1) is performed. However, the power control unit 12A reduces the LD light current for B light by a certain value Id2, does not fall below the lower limit current IL, that is, does not reach the lower limit (step S3).
10; No), the LD current for B light is decreased by a constant value Id2 (step S320),
The process returns to step S110. When the B light LD current is decreased by a certain value Id2, the current falls below the lower limit current IL, that is, the lower limit is reached (step S310; Yes).
The power control unit 12A stops the power supply from the supply unit 13 (step S260).
Then, the power control process is terminated.
As described above, each time the power control process is performed, the power control unit 12A is supplied to each of the first light emitter 2110 and the second light emitter 2210 so that the color ratio falls within the allowable value. To control the power.

Here, when the power control process is not performed as in the configuration in the first embodiment, for example, when the rate of decrease in the output level of light from the second light emitter 2210 becomes large due to product variation or the like, As the time elapses, the output level of the second light becomes lower than the output level of the first light, and the white balance is lost. Even in such a case, by performing the power control process, the output level of the first light is not decreased until the LD light current for the B light reaches the upper limit current I0, but the second light is not reduced. Since the white balance can be returned to the initial state by increasing the output level, the decrease in the output level as the combined light can be reduced even when the white balance is in the initial state.

In this power control process, the output level of the first light of the combined light is not reduced until the LD current for the B light reaches the upper limit current I0. Because it includes wavelengths that have a higher relative visibility than the second light, it suppresses the visual impact compared to reducing the first light output level without increasing the second light output level. Can also maintain white balance efficiently.
In this power control process, an unexpected failure or the like occurs in the first light source unit 210 or the second light source unit 220, and the output level of the first light or the second light is much higher than that of the other light. In such a case, the supply of the excitation LD current and the B light LD current can be stopped.

<Modification>
As mentioned above, although embodiment of this invention was described, this invention can be implemented in various aspects as follows.
[Modification 1]
In the first and second embodiments described above, the first light emitter 2110 and the second light emitter 221 are used.
0 is an LD that outputs light of the same wavelength, but may be an LD that outputs different wavelengths. Considering mass productivity, the cost can be reduced by using the same type of LD that outputs light of the same wavelength. On the other hand, for example, the first light emitter 2110 (excitation LD)
), The first luminous body 2 used for the excitation LD array light source 211 is assumed to output light having a wavelength (for example, lower wavelength side) at which the conversion efficiency of the phosphor 212 to fluorescence becomes higher.
Cost reduction by reducing the number of 110 can be achieved.
Note that, even when the first light emitter 2110 and the second light emitter 2210 output different wavelengths, when the power is continuously supplied under the same conditions, the rate of decrease in the output level of light from each of the first light emitter 2110 and the second light emitter 2210 is approximately one. It is desirable to do it.

[Modification 2]
In the first and second embodiments described above, the first light source unit 210 converts the light from the excitation LD array light source 211 into fluorescence in the phosphor 212 and outputs it as the first light.
The structure which does not use the fluorescent substance 212 may be sufficient. That is, the first light output from the first light source unit 210 and the second light output from the second light source unit 220 have the same output level reduction rate relationship as in the above-described embodiment. If so, the first light and the second light may be output in any manner.
For example, the first light emitter 2110 and the second light emitter 2210 may be LEDs instead of LDs, and even if a light source that is not a LD and is not a solid light source such as an LED is used, the first light and the third light emitter It is only necessary that the reduction rate of the light output level has the above relationship.

[Modification 3]
In the first embodiment, the power supplied to the second light emitter 2210 is the first light emitter 211.
The first light emitter 2110 and the second light emitter 2210 were 95% of the power supplied to 0.
Depending on the deterioration characteristics, the ratio may not be 95%. It is only necessary to control the power supplied to each so that the rate of decrease in the output level of the first light and the rate of decrease in the output level of the second light have substantially the same magnitude. The same applies to the power that is the initial value before the power control process determined in the second embodiment.

[Modification 4]
In the first and second embodiments described above, the wavelength included in the first light has a higher relative visibility than the wavelength included in the second light. If there is, the white balance can be efficiently maintained while suppressing the influence on the vision, but the relationship is not limited to this, and the relative luminous sensitivity may be higher for the wavelength included in the second light.

[Modification 5]
In the second embodiment described above, the detection unit 260 outputs the output level from the combined light after the first light and the second light are combined and before being separated into R light, G light, and B light. R to detect
Although it is a GB color sensor, it may be a first optical sensor that detects the output level of the first light and a second optical sensor that detects the output level of the second light. In this case, the first optical sensor is the first optical sensor between the dichroic mirror 2301C and the collimating lens 214.
The light output level of the dichroic mirror 230 is detected by the second light sensor.
The output level of the second light between 1C and the collimating lens 224 may be detected.
In any case, since the light is condensed at the phosphor 212 and the diffusion plate 222, the output level of light from each of the plurality of first light emitters 2110 and from each of the plurality of second light emitters 2210 Detection is possible with the light output level averaged.

In addition, the detection unit 260 may be installed at one location even if it is a photosensor installed at a plurality of locations as long as it is configured to detect the output level of the first light and the output level of the second light. R
A GB color sensor may be used. Since the power control unit 12A uses the ratio of the output levels of the first light and the second light, if the power control unit 12A is installed in one place, it does not need to consider sensor mounting errors. Good. On the other hand, when installed at a plurality of locations, the first light and the second light can be received separately, so that an optical sensor having the same detectable wavelength band can also be used.

[Modification 6]
In the first and second embodiments described above, the light source device including the first light source unit 210, the second light source unit 220, and the light guide unit 230 is used in the projectors 2000 and 2000A. It may be used as a backlight. In this case, the light guide unit 230 corresponds to a light guide plate, a diffusion plate, or the like.

[Modification 7]
In the first and second embodiments described above, the number of the first light emitters 2110 and the second light emitters 2210 and the power supplied to these are determined so that the white balance is maintained. The color is not limited to white as long as the color balance is maintained.

10R, 10G, 10B ... drive circuit, 11 ... modulation control unit, 12, 12A ... power control unit, 1
DESCRIPTION OF SYMBOLS 3 ... Supply part, 131 ... LD drive part for excitation, 132 ... LD drive part for B light, 100R, 100
G, 100B ... display panel, 2000, 2000A ... projector, 210 ... first light source section, 211 ... excitation LD array light source, 2110 ... first light emitter, 212 ... phosphor, 213 ...
Condensing lens, 214 ... Parallelizing lens, 220 ... Second light source section, 221 ... LD array light source for B light, 2210 ... Second light emitter, 222 ... Diffuser, 223 ... Condensing lens, 224 ... Parallelizing lens, 230: Light guide unit, 2301C, 2301S ... Dichroic mirror, 2302 ... Mirror, 2303 ... First multi lens, 2304 ... Second multi lens, 2305 ... Polarization conversion element, 2306 ... Superimposing lens, 2307 ... Lens, 2308 ... Condensing Lens, 240 ... Dichroic prism, 250 ... Projection lens, 260 ... Detector, 3000 ... Screen

Claims (9)

A first light source unit that has a first light emitter that outputs light when power is supplied, and that outputs first light using the first light emitter;
A second light source unit that has a second light emitter that outputs light when power is supplied, and that outputs second light using the second light emitter;
A light guide for guiding the first light and the second light with respect to a light valve that modulates light;
A supply unit for supplying power to the first light emitter and the second light emitter,
The reduction rate of the output level of the second light when the power of the specific value is continuously supplied to the second light emitter is the first rate when the power of the specific value is continuously supplied to the first light emitter. Greater than the rate of decrease of the light output level of 1,
The power supplied to the second light emitter by the supply unit is supplied to the first light emitter by the supply unit.
It is set so that it may become less than the electric power supplied to a light-emitting body. The light source device characterized by the above-mentioned. The first light source unit has a phosphor that emits fluorescence as the first light when irradiated with light from the first light emitter, and whose conversion efficiency to fluorescence increases when the amount of excitation light decreases. The light source device according to claim 1. A detector for detecting a first output level of the first light and a second output level of the second light;
By controlling the supply unit, power is supplied to the second light emitter so that the relationship between the first output level and the second output level detected by the detection unit becomes a predetermined setting relationship. The light source device according to claim 1, further comprising: a power control unit that controls the light source device. The power control unit is supplied to the second light emitter when the power supplied to the second light emitter for setting the relationship to the setting relationship exceeds a predetermined threshold value. 4. The light source device according to claim 3, wherein power supplied to the first light emitter is reduced instead of power control. 5. When the power supplied to the first light emitter or the second light emitter for making the relationship the setting relationship is lower than a predetermined threshold, the power controller The light source device according to claim 4, wherein supply of electric power from is stopped. The power control unit performs control of power supplied from the supply unit by controlling a value of a current or a duty ratio supplied with the supply of the power. The light source device according to any one of the above. The wavelength included in the first light includes a wavelength having a higher relative visibility than the wavelength included in the second light. The light source device described. When the power of a specific value continues to be supplied to the first light emitter, the reduction rate of the output level of light output from the first light emitter and the power of the specific value continues to be supplied to the second light emitter. The light source device according to any one of claims 1 to 7, wherein a reduction rate of the output level of the light output from the second light emitter is substantially the same. A light source device according to any one of claims 1 to 8,
The light valve;
A projector comprising: a modulation control unit that controls light modulation contents in the light valve in accordance with an input video signal.

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