The guard method of optical projection system, ager and device
Technical field
The present invention relates to the control or the regulation technology of high power light source, relate in particular to, such as the protection of colour wheel or fluorescent powder ager.
Background technology
Typical projection display system comprises light-source system, and this light-source system comprises some monochromatic sources, such as but not limited to red light source, green light source and blue-light source, produces ruddiness (R), green glow (G) and blue light (B) light beam respectively.Described projection display system also comprises being used for modulating to be made described red, green, blue light beam produce the light valve of coloured image and is used for throwing red, green, blue light beam after described light valve modulation to the optical projection camera lens of screen with the generation image.Described red, green, blue light beam can but be not limited to conduct to color-combination prism by optical fiber, after converging, transport to light valve.Described light valve can be microelectromechanical-systems (MEMS, a micro-electron-mechanical system) equipment, for example based on the photomodulator of the DLP of company of Texas Instrument (TexasInstrument) (Digital Light Processing) technology.The image-signal processor of projection display system is controlled each light source by drive signal, and exports corresponding view data toward photomodulator.For example, when red-light source is unlocked and during red-emitting, image-signal processor will red image data be sent to photomodulator (digital micro-mirror device for example, DMD); Similarly, when green glow or blue light source be unlocked and launch green/during blue light, image-signal processor will be sent to photomodulator to green accordingly/blue image data.If when all red, green and blue radiants all are unlocked, the gray image data will be sent to photomodulator.Wherein, light-source system can also provide feedback signal toward image-signal processor, forms with described drive signal to be used for the feedback control loop of stabilized light source colourity and brightness.Image beam after the modulation projects display screen via described optical projection camera lens at last.
Existing light-source system is for saving cost, and adopt UHP (very-high performance) lamp in early days is that light source produces white light more; By ager, for example the segmentation colour wheel comes transmission to produce and shows required monochromatic light such as red, green, blue again.The weak point of this scheme is: the UHP lamp starts needs higher trigger voltage, often up to thousands of volts; And the startup of UHP lamp is with to close the stand-by period longer; Each the monochromatic light color effect that adopts this scheme to produce is poor, and gamut range is less.
Along with the development of LED (Light Emitting Diode, light emitting diode) technology, the more and more LED that adopt of light-source system overcome above-mentioned deficiency.
Can be divided into following several (for sake of convenience, light emitting source is example with LED) with having light-source system now by monochromatic producing method:
1) adopt the LED of different colours to produce various homogeneous beams respectively, for example red, green, blue, gold-tinted bundle.This mode display effect is good, and gamut range is wide, but the LED cost is higher.
2) adopt monochromatic LED and ager to produce various homogeneous beams.Modal ager is the segmentation colour wheel.As shown in Figure 1, described colour wheel 20 is placed the emergent light light path of LED 10, thereby light comes timesharing to produce the corresponding monochromatic light of color with each segmentation with transmission mode via the colour wheel that is rotating.
3) adopt the ager of monochromatic LED and band optical wavelength conversion material to produce various homogeneous beams.Described optical wavelength conversion material comprises fluorescent powder.Usually segmentation is coated with fluorescent powder and realizes the segmentation toning between the double glazing of colour wheel.Described glass itself can be high temperature resistant, and the temperature extremes that fluorescent powder can bear is generally 100~200 ℃.Under the irradiation of described LED, can come the corresponding monochromatic stimulated luminescence of fluorescent powder of timesharing acquisition and each segmentation by the rotation of described colour wheel.For example tricolor projection's display system normally produces based on blue-ray LED and shows required red, green, blue monochromatic light.Sometimes can add the common excitated fluorescent powder of ultraviolet LED with blue-ray LED for the launching efficiency that improves fluorescent powder.
Above-mentioned the deficiencies in the prior art part is: along with market is increasing to the power requirement of light-source system, various high-power light sources continue to bring out, and make the ager in the light-source system receive increasing luminous energy.When shown in ager (for example colour wheel) when being in high-speed motion, these luminous energies can not concentrated and accumulate in a fixed segments in the unit interval.But if occur unexpected, optical-mechanical system reason such as break down for example, when unexpected stall of colour wheel or rotating speed are significantly reduced, these luminous energies will make colour wheel gather too high heat because of the part to burn or cause the permanent inefficacy of coated optical wavelength conversion material in the unit interval.Also have a kind of possibility in addition: colour wheel also should start after projector started under the normal condition; But if because of certain unexpected colour wheel does not start thereupon, system then can cause damage to colour wheel or fluorescent powder usefulness equally in a short period of time if also start led light source in the normal order at this moment.
Summary of the invention
The technical problem to be solved in the present invention is at above-mentioned the deficiencies in the prior art part, and proposes a kind of guard method and device, is used for projection display system, can make ager exempt from the high power light irradiation and impaired or breaking-up.
For solving the problems of the technologies described above; of the present inventionly be contemplated that substantially: if the motion that a device is monitored ager in real time is set; the rotating speed of colour wheel for example; when finding that rotating speed is low when being enough to endanger fluorescent powder effect or colour wheel proterties; cut off the power supply source of light emitting source rapidly, then can reach the purpose of protection colour wheel or fluorescent powder.Specifically, be included in the optical projection system startup and in the optical projection system course of normal operation,, then do not open described power supply source if monitoring the colour wheel rotating speed is lower than preset value; Recover just often when monitoring or monitor once more rotating speed, open described power supply source, be convenient to the optical projection system trouble free service.
As the technical scheme that realizes the present invention's design be, a kind of guard method of ager be provided, be used for light-source system, comprising:
Give the step of the light emitting source power supply of this light-source system; Light from this light emitting source is exported by an optical channel;
Control makes the step of the ager motion that is arranged on the described optical channel; Described ager comprises at least two zones with different optical characteristic, and the motion of this ager makes each described zone constantly enter described optical channel by turns; Especially, also comprise step:
Monitor the motion of described ager, little or when equaling a predetermined value when the speed that measures described motion, cut off power supply to described light emitting source; Otherwise, start or keep power supply described light emitting source.
In the such scheme, described light-source system starts the step of the motion of the described ager of monitoring earlier, controls and carries out the step of giving described light emitting source power supply.Then can start and begin colour wheel and fluorescent powder are protected from light source.
In the such scheme, in a single day described light-source system powers on, and carries out the step of the motion of the described ager of monitoring all the time.Then be convenient to after the ager fault is got rid of the work of instant recovery light-source system.Described ager is a moving coil.
In the such scheme, described different optical characteristic or be meant different transmissions or the reflection characteristic of described zone to identical incident light; Or when on one of described zone, carrying optical wavelength conversion material, refer to the different light wavelength conversion characteristics of described zone to identical incident light.
In the such scheme, described optical wavelength conversion material is carried on the described zone by the form with coating, filling or pad pasting.
In the such scheme, when monitoring the motion of described ager, be that a location device is set on described ager, be used to provide a reference signal of assessing this ager movement velocity according to this and carry out described monitoring for the control module of described light-source system.
Described locating device is included in the servomechanism installation of described ager, and described reference signal is the angle or the position coherent signal of the output of this servomechanism installation.Or described locating device is a projection that is installed in described ager edge, and the motion of this ager makes this projection periodically trigger light or dynamo-electric detection signal, is used as described reference signal.
In the such scheme, described control module is to assess described ager movement velocity according to the pulsewidth of described reference signal, or assesses described ager movement velocity according to the umber of pulse of described reference signal in the unit interval.
As the technical scheme that realizes the present invention's design still, provide a kind of protective device of ager, be used for light-source system, this light-source system comprises light emitting source and ager, projects described ager from the light of described light emitting source by an optical channel; This ager comprises at least two zones with different optical characteristic, and when this ager is kept in motion, each described zone will constantly enter the projection scope of described optical channel by turns; Especially, described protective device comprises that a control module and is arranged on the locating device on the described ager; Described locating device provides a reference signal that changes with the motion of this ager to described control module; This control module is exported the power switch that a control signal is given described light emitting source.
In the such scheme, described control module also connects the output terminal of a temperature sensor; This temperature sensor senses is from the variation of ambient temperature of the heat abstractor of described light emitting source and export corresponding temperature signal.
In the such scheme, described ager is a moving coil, has at least two zones that are different light transmission features; Or have at least two zones that are different light wavelength conversion characteristics, wherein at least one regions carry has optical wavelength conversion material.
As the technical scheme that realizes the present invention's design still, provide a kind of optical projection system, comprise light-source system, this light-source system comprises light emitting source and ager, projects described ager from the light of described light emitting source by an optical channel; This ager comprises at least three zones with different optical characteristic, when this ager is kept in motion, each described zone will constantly enter the projection scope of described optical channel by turns, thereby this light-source system provides the some homogeneous beams that comprise ruddiness, green glow and blue light; This optical projection system also comprises being used for modulating to be made described red, green, blue light beam produce the light valve of coloured image and is used for throwing red, green, blue light beam after described light valve modulation to the optical projection camera lens of screen with the generation image; This optical projection system also comprises image-signal processor, and this image-signal processor is controlled the light output of light-source system by drive signal, and exports corresponding view data toward described light valve; Especially, described optical projection system comprises that also a control module and is arranged on the locating device on the described ager; Described locating device provides a reference signal that changes with the motion of this ager to described control module; This control module is exported the power switch that a control signal is given described light emitting source.
In the such scheme, described control module also connects the output terminal of a temperature sensor; This temperature sensor senses is from the variation of ambient temperature of the heat abstractor of described light emitting source and export corresponding temperature signal.
In the such scheme, described control module measures the environment temperature of this temperature signal representative or temperature variation when surpassing a predetermined warning value, produces the control signal of reporting to the police for the system of selling.
In the such scheme, described ager comprises having at least trizonal colour wheel that be different light transmission features corresponding respectively mutually with described ruddiness, green glow and blue light; Or comprise having at least trizonal colour wheel with different light wavelength conversion characteristics corresponding respectively mutually with described ruddiness, green glow and blue light, carry two kinds of optical wavelength conversion materials that distribute by zones of different on this colour wheel at least.
Adopt above-mentioned each technical scheme, all can play a protective role, have the low advantage of the cost of realization simultaneously ager.
Description of drawings
Fig. 1 is existing known luminaire system light path structural representation;
Fig. 2 is to be the light-source system structural representation of the present invention of example with the rotating disk;
Fig. 3 is one of the light channel structure alternative embodiment of a light-source system of the present invention synoptic diagram;
Fig. 4 is two synoptic diagram of the light channel structure alternative embodiment of light-source system of the present invention;
Fig. 5 is three synoptic diagram of the light channel structure alternative embodiment of light-source system of the present invention;
Fig. 6 is the structural representation of optical projection system of the present invention;
Wherein, each Reference numeral is: 10---light emitting source, and 11---excitation line, 11 '---the conversion light of excitation line; 20---ager/colour wheel, 21---locating device; 30---lens; 41,42---photo-detector.
Embodiment
Below, the most preferred embodiment shown in is further set forth the present invention in conjunction with the accompanying drawings.
Existing known luminaire system as Fig. 1 representative comprises light emitting source 10 and colour wheel 20, projects described colour wheel 20 from the light of described light emitting source 10 by (for example lens 30 an are guided) optical channel; This colour wheel 20 comprises at least two zones with different optical characteristic, four zones of 20a, 20b, 20c and 20d representative for example with different light transmission features, when this colour wheel is kept in motion, each described zone will constantly enter the projection scope of described optical channel by turns, thereby the timesharing transmission produces different monochromatic light.
When carrying different optical wavelength conversion material respectively with the form of coating, filling or pad pasting on four zones at described colour wheel 20, to have different light wavelength conversion characteristics between each zone, will be transformed into light 11 ' to the excitation line 11 that comes self-emitting light source 10 by turns with different wave length thereby each zone enters optical channel by turns.Can allow to have in described each zone one (for example 20a) or more than one (for example 20a and 20c) do not carry any optical wavelength conversion material and lead directly to described excitation line 11.
The present invention designs and provides several embodiment in order to replacement Fig. 1 light channel structure according to the application scenario of light source.
One of embodiment shown in Figure 3 matches described colour wheel 20 with catoptron, be equal to reflection and replace described transmission, changes optical path direction.Because of this replaces with prior art, do not reach and hereinafter give unnecessary details at this.
Two of embodiment shown in Figure 4 replaces described colour wheel 20 with the rotating cylinder that is made of transparent material, the surface of revolution of described rotating cylinder is become three zones along the tube fate, and light emitting source 10 provides excitation line and directed toward a projected area by optical channel (not illustrated) in the inside of described rotating cylinder 20.
Three of embodiment shown in Figure 5 replaces described colour wheel 20 with the rectangle displacement disc that is made of opaque material, and this displacement disc moves as linear reciprocation, is divided into three zones, by this displacement disc the reflex of light is changed described optical channel direction.
Above-mentioned several embodiment is not exhaustive to the structure of light-source system of the present invention, and other structure of deferring to inventive concept also will be in protection scope of the present invention.Therefore, for setting forth for purpose of brevity, hereinafter if not otherwise stated, ager will comprise the moving coil with at least two zones that are different light transmission features, or have the moving coil (wherein at least one regions carry has optical wavelength conversion material) at least two zones that are different light wavelength conversion characteristics; Described moving coil comprises rolling disc or displacement disc; Described optical wavelength conversion material comprises fluorescent powder, dyestuff or quantum dot; Described light emitting source comprises led light source, LASER Light Source or UHP (very-high performance) lamp.
Control generally comprises step based on the process that the light-source system of said structure carries out work:
A. give the light emitting source power supply of this light-source system; Light from this light emitting source is exported by an optical channel;
B. control makes the ager motion that is arranged on the described optical channel; Described ager comprises at least two zones with different optical characteristic, and the motion of this ager makes each described zone constantly enter described optical channel by turns;
Based on above-mentioned steps, the present invention proposes to be used for protecting the method for ager to be: monitor the motion of described ager, and little or when equaling a predetermined value when the speed that measures described motion, cut off power supply to described light emitting source.
Can't move and light emitting source is started working ager is caused damage for fear of light-source system power supply back ager, the execution order that the present invention can further adjust above steps is: described light-source system starts the step of the motion of the described ager of monitoring earlier, controls and carries out the step of giving described light emitting source power supply.Promptly the power supply controlled step of light emitting source is adjusted into by monitoring result and starts, system powered could for described light emitting source after only motion and movement velocity were monitored to rationally after ager is controlled.
When described light emitting source adopts LED,, carry out the step of the motion of the described ager of monitoring all the time in case described light-source system can be arranged to power on.Like this, after system cut off the LED power supply because of certain reason, described control module continued the motion of the described ager of monitoring, was convenient to after this reason eliminating, measure the recovery (to greater than described predetermined value) of described movement velocity as early as possible, and then recover power supply described light emitting source.
Concrete monitoring measure can be: a location device is set on described ager, is used to provide a reference signal of assessing this ager movement velocity according to this and carries out described monitoring for the control module of described light-source system.With Fig. 3 is example, and described locating device can be set to be installed in a projection 21 at described ager 20 edges; A photodetector or an electromechanical detection device of aiming at the precalculated position is set outside described ager 20, when the rotation period ground of described ager 20 drives described projection 21 these precalculated positions of arrival, periodically one of triggering for generating detects pulse, is used as described reference signal.
The colour wheel that is higher than 7200 rpms with general rotating speed in the optical projection system is an example, suppose the words that described control module is realized with a single-chip microcomputer, can make that this control module is the umber of pulse that occurs in the described reference signal of unit interval in the second, thereby assess out the rotating speed of described colour wheel.When finding that described umber of pulse is reduced to a predetermined value, mean the degree that rotating speed has been reduced to is enough to endanger fluorescent powder effect or colour wheel material, should cut off power supply rapidly to described light emitting source.Described predetermined value comes experience to determine according to concrete colour wheel or phosphor material powder.Described single-chip microcomputer can also be by FPGA (Field ProgrammableGate-Array field programmable gate array), CPLD (Comlpex Programmable Logic Device, CPLD) or DSP (Digital Signal Processor, digital signal processor) etc. replace.
The minimum precision of above-mentioned monitoring is 1 second, still might cause damage for some comparatively fragile fluorescent powder.For this reason, can utilize the correlativity of each pulse pulsewidth and colour wheel rotating speed, make described control module calculate each pulse pulsewidth in real time,, cut off power supply rapidly described light emitting source when the pulsewidth of the pulsewidth that monitors a pulse or continuous a plurality of pulses during greatly to a predetermined value.
Because the fault of described ager may be undesired and cause by the servomechanism installation work of this ager, and described rolling disc or displacement disc produce under the effect of servomechanism installation when moving, described servomechanism installation might be exported the relevant signal of an angle or position, therefore, a part that can described locating device be set to this servomechanism installation is used as described reference signal with the relevant signal of described angle or position.
In addition, as shown in Figure 4: described locating device can also be mounted in reflection of one in the described ager or absorption plant (a for example reflex block 21 that is provided with at the rotating cylinder inwall); Static installation one photoemission and receiving trap outside ager are emitter with described light emitting source double as for example simultaneously, and a photodetection receiving trap 41 is set again; The motion of this ager makes this photoemission and receiving trap connect or be blocked by described reflex block 21, to produce described reference signal.
Or this locating device is a photoelectric probe that is installed in the edge of the outer emitting light path of described ager, shown in the photo-detector 42 of Fig. 4, the detection sensitivity of this probe changes with the difference of optical wavelength, thereby with the motion of described telecontrol equipment the variation of this probe output is used as described reference signal.Correspondingly, adjust the mode that control module is discerned this reference signal and assessed described ager movement velocity.
Described locating device can also be mounted in the linear or circular grating chi in the described ager, and a photoelectric probe also is installed outside described ager, thereby directly provides reference signal corresponding to diverse location by " reading " this grating chi.
According to the inventive method, the protective device that the present invention design is used for protecting the light-source system ager comprises that a control module and is arranged on the locating device (not illustrated) on the described ager as shown in Figure 2.Described locating device provides a reference signal that changes with the motion of this ager to described control module; This control module is exported the power switch that a control signal is given described light emitting source, thereby this control module is assessed the movement velocity of described ager according to described reference signal and provide corresponding described control signal to cut off or open power supply to described light emitting source.
The optical projection system of using guard method of the present invention and device is example with 6 specific embodiment, comprises light-source system, and this light-source system comprises light emitting source and ager, projects described ager from the light of described light emitting source by an optical channel; This ager comprises at least three zones with different optical characteristic, when this ager is kept in motion, each described zone will constantly enter the projection scope of described optical channel by turns, thereby this light-source system provides at least three kinds of homogeneous beams that comprise ruddiness, green glow and blue light.When described optical characteristics referred to printing opacity (transmission or reflection) characteristic to identical incident light, described ager comprised having at least trizonal colour wheel that be different light transmission features corresponding respectively mutually with described ruddiness, green glow and blue light.When described optical characteristics refers to different light wavelength conversion characteristic to identical incident light, described ager comprises having at least trizonal colour wheel with different light wavelength conversion characteristics corresponding respectively mutually with described ruddiness, green glow and blue light, carries two kinds of optical wavelength conversion materials that distribute by zones of different on this colour wheel at least.That is to say,, allow to have among regional a, b, c and the d two zones to have identical optical characteristics and corresponding identical monochromatic light output the colour wheel embodiment of Fig. 6; And allow to have at least a zone not use optical wavelength conversion material, the just straight-through light that is used to from described light emitting source.Require to export indigo plant, green, yellow, red four look homogeneous beams respectively by described regional a, b, c and d under the occasion in higher color.
Described optical projection system also comprises and is used for modulating the light valve that makes described red, green, blue light beam produce coloured image, for example illustrated digital micro-mirror device (DMD); Be used for throwing red, green, blue light beam after described light valve modulation to the optical projection camera lens of screen with the generation image; Also comprise image-signal processor, this image-signal processor is controlled the light output of light-source system by drive signal, and exports corresponding view data toward described light valve.
Described optical projection system comprises that also a control module and is arranged on the locating device on the described ager; In this Fig. 6 embodiment, described control module can be an internal element of described image-signal processor.Described locating device provides a reference signal that changes with the motion of this ager to described control module; This control module is exported the power switch that a control signal is given described light emitting source.
In this optical projection system, be example with the LED light emitting source, will only some change into luminous energy in the resulting electric energy, and must have another part to convert heat energy to.In order to guarantee the operate as normal of LED, usually a heat abstractor can be set on the back side such as but not limited to the LED metal substrate.Under some particular conditions, lost efficacy such as this heat abstractor, then the LED cause thermal damage that will rise rapidly because of the temperature that self-heating causes can't normally show optical projection system.For this reason, shown in the dotted line of Fig. 2, can also monitor a temperature signal simultaneously on the control module of optical projection system described in the present invention.This control module can connect the output terminal of a temperature sensor (not illustrated); This temperature sensor senses is from the variation of ambient temperature of described heat abstractor and export corresponding temperature signal.Described control module measures the environment temperature of this temperature signal representative or temperature variation when surpassing a predetermined warning value, produces the control signal of reporting to the police can for the system of selling; When reaching one may damage the predetermined critical of light emitting source the time, export a control signal and give the power switch of described light emitting source thoroughly to cut off the electricity supply, to guarantee the safety of light emitting source.
Described temperature sensor when for example adopting heat-sensitive element, can directly be installed on the substrate of described LED light emitting source, thereby change with the changes in resistance size of environment temperature.Described temperature signal is actual to be sampling voltage or the sampling current signal relevant with this heat-sensitive element.This signal can be simulating signal or digital signal, can determine whether according to the interface requirement of described control module carrying out corresponding signal transformation.Described temperature sensor can also adopt the sensor of other type and adjust corresponding signal type.Because these are prior art, repeat no more.
Experiment showed, and use the light-source system or the optical projection system of the inventive method to change under the little prerequisite, realize protection effectively fluorescent powder or colour wheel at hardware.