WO2022052867A1 - 投影设备 - Google Patents

投影设备 Download PDF

Info

Publication number
WO2022052867A1
WO2022052867A1 PCT/CN2021/116379 CN2021116379W WO2022052867A1 WO 2022052867 A1 WO2022052867 A1 WO 2022052867A1 CN 2021116379 W CN2021116379 W CN 2021116379W WO 2022052867 A1 WO2022052867 A1 WO 2022052867A1
Authority
WO
WIPO (PCT)
Prior art keywords
laser unit
current
life
image frame
time
Prior art date
Application number
PCT/CN2021/116379
Other languages
English (en)
French (fr)
Inventor
余新
胡飞
李屹
Original Assignee
深圳光峰科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 深圳光峰科技股份有限公司 filed Critical 深圳光峰科技股份有限公司
Publication of WO2022052867A1 publication Critical patent/WO2022052867A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3141—Constructional details thereof
    • H04N9/315—Modulator illumination systems
    • H04N9/3161—Modulator illumination systems using laser light sources
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • G03B21/2006—Lamp housings characterised by the light source
    • G03B21/2033—LED or laser light sources
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings
    • G03B21/206—Control of light source other than position or intensity
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3141—Constructional details thereof
    • H04N9/315—Modulator illumination systems
    • H04N9/3155—Modulator illumination systems for controlling the light source
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/31—Projection devices for colour picture display, e.g. using electronic spatial light modulators [ESLM]
    • H04N9/3179—Video signal processing therefor

Definitions

  • the present invention relates to the technical field of projection display, and more particularly, to a projection device.
  • HDR high dynamic range
  • one solution to realize the HDR projection system is to use the Local Dimming (regional dimming) technology of the LCD backlight.
  • the technical solution uses a laser array as the light source of the projection equipment, each laser is responsible for the illumination of an area, and during the projection display, the luminous intensity of each laser light source is dynamically controlled according to the brightness of each area of the projection screen, so as to achieve high-contrast display. .
  • the attenuation of the lasers irradiating different areas is different, so the remaining lifetimes of the lasers in different areas are different after playing the image for a period of time. Therefore, how to balance the brightness and life of the light source is an urgent problem to be solved.
  • Embodiments of the present invention provide a projection device to improve the above problems.
  • An embodiment of the present invention provides a projection device, including a light source device, a spatial light modulator, and a control device;
  • the light source device includes at least one laser unit;
  • the control device is configured to obtain brightness distribution information of a current image frame according to an image signal to be displayed, and adjust the driving current of the laser unit according to the brightness distribution information of the current image frame and the life data information of the laser unit, so that the adjusted actual driving current is greater than the rated driving current during at least part of the current image frame time;
  • the spatial light modulator is set On the optical path of the light emitted by the light source device, it is used to modulate the light emitted by the light source device to obtain a modulated image.
  • control device is used to determine the ideal driving current of the laser unit according to the brightness distribution information of the current image frame, and adjust the ideal driving current of the laser unit according to the life data information of the laser unit to obtain the actual driving current.
  • the life data information of the laser unit includes the consumed life and the used time of the laser unit.
  • the control device adjusts the driving current of the laser unit to make the adjusted actual driving current. At least part of the time period within the current image frame time is greater than the rated drive current.
  • the actual driving current of the laser unit within the current image frame time is less than or equal to the maximum off current of the laser unit.
  • the maximum off current of the laser unit is determined by the consumed life of the laser unit and the ratio of the consumed life and the used time of the laser unit.
  • the lifetime decay rate of the laser unit under the actual driving current during the current image frame time is less than or equal to the maximum single-frame lifetime decay rate of the laser unit driven by the maximum off current.
  • the maximum single-frame lifetime decay rate of the laser unit is a certain value after using the preset time.
  • the maximum single-frame lifetime decay rate of the laser unit within the current image frame time is determined by the maximum lifetime consumption rate of the current usage time of the laser unit and the maximum lifetime consumption rate when the designed lifetime of the laser unit arrives.
  • the maximum single-frame lifetime decay rate of the laser unit within the current image frame time is r D :
  • L T is the used time of the laser unit
  • L d is the design life of the laser unit
  • a is the maximum life decay rate of the laser unit when the use time is LT
  • b is the maximum life of the laser unit when the use time reaches the design life Lifetime decay rate.
  • control device is further configured to calculate the lifetime consumption information of the laser unit within the current image frame time, so as to update the lifetime data information of the laser unit.
  • control device is used to calculate the lifespan consumed by the laser unit in the current image frame; and subtract the lifespan consumed by the laser unit in the current image frame from the remaining lifespan of the laser unit before the playback of the current image frame to obtain the laser unit. Updated life data information.
  • the light source device includes at least one laser unit, and when each frame of image is displayed, the control device adjusts the driving current of the laser unit according to the brightness distribution information of the current image frame and the life data information of the laser unit , so that the adjusted actual drive current is greater than the rated drive current for at least part of the current image frame time, so that the laser unit outputs high-brightness light for modulation by the spatial light modulator.
  • the life of the laser unit determines the drive current of the laser unit, making full use of the relationship between the life of the laser unit and the drive current, so that the laser unit works intermittently under the condition of exceeding its rated drive current to output light with higher peak brightness at the same time. It does not affect the service life of the system, and can ensure that the light source device can achieve high-brightness display under the condition that the service life requirement is met.
  • FIG. 1 shows a block diagram of a projection device according to an embodiment of the present invention.
  • FIG. 2 shows a schematic diagram of functional modules of a control device of a projection device according to an embodiment of the present invention.
  • FIG. 3 shows a working flowchart of a projection device provided by an embodiment of the present invention.
  • FIG. 1 shows a block diagram of a projection device 100 provided by an embodiment of the present invention.
  • the projection device 100 may be, but is not limited to, a laser TV, an educational projector, a micro-projector, a theater projector, and other devices with projection functions.
  • the device may also be a computer system connected to a device with a projection function and using the distance measuring sensor of the device, such as a personal computer, notebook computer, tablet, smart phone, etc. connected to the projection device.
  • the projection direction of the projection device in the embodiment of the present application is not limited, and it may be rear projection or front projection.
  • the projection apparatus 100 includes a control device 10 , a light source device 30 and a spatial light modulator 40 .
  • the light source device 30 includes at least one laser unit;
  • the control device 10 is used to obtain the brightness distribution information of the current image frame according to the image signal to be displayed, and adjust the driving of the laser unit according to the brightness distribution information of the current image frame and the life data information of the laser unit current, so that the adjusted actual driving current is greater than the rated driving current in at least part of the current image frame time;
  • the spatial light modulator 40 is arranged on the optical path of the light emitted by the light source device Modulation is performed to obtain a modulated image.
  • the light source device 30 includes at least one laser unit, and when displaying each frame of image, the control device 10 adjusts the driving current of the laser unit according to the brightness distribution information of the current image frame and the life data information of the laser unit, The adjusted actual drive current is greater than the rated drive current for at least part of the current image frame time, so that the laser unit outputs high-brightness light for modulation by the spatial light modulator 40.
  • the life of the laser unit determines the drive current of the laser unit, making full use of the relationship between the life of the laser unit and the drive current, so that the laser unit works intermittently under the condition of exceeding its rated drive current to output light with higher peak brightness at the same time. It does not affect the service life of the projection apparatus 100, and can ensure that the light source device 30 can achieve high-brightness display under the condition that the service life requirements are met.
  • the projection apparatus 100 further includes a light source driver and an imaging element.
  • the light source driver is respectively connected with the control device 10 and the light source device 30, the control device 10 is used for receiving the image signal to be displayed, and generates a control signal according to the image signal to be displayed, the light source driver is used for receiving the control signal sent by the control device 10, and
  • the driving current for driving the light source device 30 is output according to the control current to light the light source device 30 , wherein the light source driver adjusts the driving current input to the light source device 30 according to the control signal to drive the light source device 30 .
  • the driving current of the light source device 30 varies with the content of the displayed image.
  • the light source device 30 is used for emitting light source light
  • the spatial light modulator 40 is used for modulating the light source light emitted by the light source device 30 according to the image signal to generate image light having a modulated image.
  • the imaging element is used to receive the image light generated by the spatial light modulator 40 and project the image light to a predetermined position or a predetermined element (such as a projection screen or a wall, etc.) to display the projected image.
  • control device 10 of the projection apparatus 100 provided by the present application will be introduced in detail below.
  • the control device 10 may include a signal processing module 11 , an adjustment module 12 and a life management module 13 , wherein the life management module 13 includes a storage unit for storing life data information of the laser unit.
  • the signal processing module 11 is used to obtain the brightness distribution information of the current image frame according to the image signal to be displayed, and to determine the ideal driving current of the laser unit according to the brightness distribution information of the current image frame, and the adjustment module 12 adjusts according to the life data information of the laser unit.
  • the ideal driving current of the laser unit is obtained to obtain the adjusted actual driving current of the laser unit, and the laser unit emits light under the driving of the actual driving current, so that the laser unit outputs light of target brightness.
  • the life management module 13 is configured to calculate the life consumption information of the laser unit in the current image frame, so as to update the life data information of the laser unit.
  • the above-mentioned modules can be program modules running in a computer-readable storage medium, and the purpose and work of each of the above-mentioned modules are as follows:
  • the signal processing module 11 is configured to obtain the brightness distribution information of the current image frame according to the image signal to be displayed, and determine the ideal driving current of the laser unit according to the brightness distribution information of the current image frame.
  • the image signal to be displayed may be stored locally in the projection device, or may be an image signal received by the projection device based on a data connection (such as a local area network data connection or a wide area network data connection, etc.).
  • the image signal can come from first storage (for example, pre-copying the audio and video data to be projected to the projection device for storage) or immediate storage (for example, inserting a mobile hard disk storing the audio and video data to be projected in the projection device for storage)
  • first storage for example, pre-copying the audio and video data to be projected to the projection device for storage
  • immediate storage for example, inserting a mobile hard disk storing the audio and video data to be projected in the projection device for storage
  • the specific storage method is not limited; the image content may be image content in a video file, image content in a picture file, etc., which is not limited in this embodiment of the present application.
  • the projection device can count the brightness distribution of the current image frame according to its own type and the image signal to be displayed.
  • the projection device may be a projection device based on the global dimming technology, and it is only necessary to count the maximum brightness value of the entire screen.
  • the maximum brightness of each area needs to be counted regionally.
  • Projection equipment using dynamic color gamut technology needs to count the maximum brightness values of different primary color lights in the entire screen.
  • a projection device using a scanning light source needs to convert the brightness distribution of the two-dimensional image into a brightness change curve on the scanning path.
  • the signal processing module 11 After acquiring the brightness distribution information of the current image frame, the signal processing module 11 generates an ideal driving current I(t) of the laser unit based on the brightness distribution information of the current image frame, and the ideal driving current I(t) represents the output light of the corresponding laser unit. ideal brightness.
  • the ideal driving current I(t) of the laser unit can be understood as the driving current when the actual working conditions and life data information of the laser unit are not considered.
  • the signal processing module 11 determines the ideal driving current I(t) of the laser unit required for displaying the current image frame based on the brightness distribution (brightness curve) of the current image frame.
  • the adjustment module 12 adjusts the ideal drive current I(t) of the laser unit according to the life data information of the laser unit to obtain the actual drive current I'(t), wherein the actual drive current I'(t) of the laser unit represents the corresponding laser unit The actual brightness of the output light.
  • the actual driving current I'(t) is greater than the rated driving current during at least part of the current image frame time, that is, the laser unit is in an overcurrent driving state during at least part of the current image frame time, so that the laser emits higher brightness. light, so as to meet the brightness requirements of HDR on the light source device.
  • the spatial light modulator 40 includes but is not limited to a digital micro-mirror device (Digital Micro-mirror Device, DMD), and may also be a liquid crystal display panel (Liquid Crystal Display, LCD) or a liquid crystal on silicon (Liquid Crystal on Silicon, LCOS).
  • DMD Digital Micro-mirror Device
  • LCD liquid crystal Display
  • LCOS liquid crystal on silicon
  • the spatial light modulator 40 uses a digital micromirror device as an example, but this is not intended to limit the scope of the present invention.
  • the spatial light modulator 40 includes a plurality of micromirror units, and each micromirror unit corresponds to one pixel of the modulated image.
  • the micromirror unit When the micromirror unit is in the "on” state, the micromirror unit reflects the light source light to the corresponding pixel area, and the corresponding The pixel is in the "bright” state, and when the micromirror unit is in the "off” state, the micromirror unit does not reflect light from the light source to the corresponding pixel area, and the corresponding pixel is in the "dark” state.
  • the light emitted by the light source device 30 is irradiated on the spatial light modulator 40, and the spatial light modulator 40 modulates the light emitted by the light source device 30 according to the image signal to be displayed.
  • the data information adjusts the ideal driving current I(t) of the laser unit, so that the adjusted actual driving current I'(t) is greater than the rated driving current during at least part of the current image frame time.
  • the brightness of the light emitted from the light source device 30 can be improved.
  • the current image frame time includes multiple bit plane modulation periods (eg, 8 bits or 10 bits).
  • the adjustment module 12 adjusts the ideal driving current I(t) of the laser unit according to the life data information of the laser unit, so that the adjusted actual driving current I(t) The drive current I'(t) is greater than the rated drive current for at least one bit-plane modulation period within the current image frame time.
  • the driving current of the laser unit is the rated driving current, and the luminous brightness of the laser unit is L, then in the at least one bit plane modulation period, the actual driving current I'(t) of the laser unit is greater than the rated driving current, and at this time the laser unit
  • the luminous brightness of ML can reach ML (M>1), so that the luminous brightness of the light source device 30 is improved during the at least one bit plane modulation period, so that each pixel of the modulated image reaches a preset grayscale value.
  • the control device 10 determines the life management strategy corresponding to the laser unit according to the life data information of the laser unit (that is, the optimization process for the ideal control current provided by the present application), so that the laser unit outputs a higher peak brightness light without affecting the service life of the system.
  • the life data information of the laser unit is used to represent factors that can affect the actual life of the laser unit, and the life data information of the laser unit includes the consumed life and the used time of the laser unit.
  • the life of the laser unit will be attenuated, that is, the remaining life of the laser unit will be reduced.
  • the consumed life of the laser unit can be determined by the display principle of the laser projection device and the actual working condition of the laser unit.
  • the laser unit works with a constant current, so the life decay rate of the laser unit is a constant value.
  • the laser unit will determine the output of the laser unit according to the maximum brightness in the screen, so the life decay rate of the laser unit is a value that changes with the working conditions, but due to all the global dimming technology
  • the laser units are uniformly changed, so the lifetime decay rate of each laser unit is the same.
  • the laser light units of different primary colors (such as blue laser for fluorescence generation, red and green laser for color compensation, etc.) Therefore, the laser units of different primary colors have different lifetime decay rates.
  • the laser units irradiating different areas have different primary color laser units, so after playing the picture for a period of time, the remaining life of the laser units in different areas is different.
  • Catastrophic optical damage is the most important factor affecting the life of a laser unit, and the life of a laser unit under high current driving is mainly determined by COD.
  • COD Catastrophic optical damage
  • the life-time L of the laser unit can be expressed as:
  • I is the continuous constant driving current of the laser unit
  • T is the working temperature of the laser unit
  • I and T are used to characterize the working conditions of the laser unit during actual operation.
  • COD occurs when the drive current I of the laser unit is greater than the COD threshold current I th (T) at that temperature, so the laser unit lifetime is 0 at this current.
  • the driving current I of the laser unit is less than the threshold current I th (T)
  • the laser unit will not generate COD.
  • the lifetime L of the laser unit can be expressed as a function of current and temperature (ie, the above formula (1)). The value of this function decreases as the driving current increases, meaning that the higher the driving current, the shorter the life of the laser unit.
  • the inherent life curve f(I, T) of the laser unit can be understood as the inherent characteristics of the laser unit, which can be preset in the projection device (for example, stored in the memory of the projection device in advance), or obtained through the aging test of the laser unit .
  • the lifetime r(I, T) consumed by the laser unit under the operating conditions (driving current I and operating temperature T) per unit time can be expressed as:
  • the over-life usage rate O(t 0 ) of the laser unit can be defined as:
  • O(t 0 ) greater than 1 indicates that the actual working condition of the laser unit during the used time t 0 exceeds the designed working condition when the design life is exceeded, and the actual life of the laser unit will be shorter than the design life if there is no subsequent change. And O(t 0 ) is less than 1, which means that the actual working condition of the laser unit during the used time t 0 does not exceed the designed working condition when the design life is not exceeded. If there is no subsequent change, the actual life of the laser unit will be longer than or equal to the design life. .
  • the control device 10 adjusts the The drive current is adjusted so that the adjusted actual drive current is greater than the rated drive current during at least part of the current image frame time, so as to achieve a balance between outputting the maximum brightness and meeting the design life.
  • the upper limit of the driving current needs to be limited.
  • the signal processing module 11 determines the overcurrent driving magnification p of the laser unit based on the ideal control current I(t) and the rated driving current I 0 of the laser unit.
  • the over-current driving magnification p of the laser unit is represented by the ratio of the ideal control current I(t) of the laser unit to the rated driving current I 0 of the laser unit, that is, the over-current driving magnification p of the laser unit can be expressed as:
  • p is less than 1, it means that the drive current of the laser unit is less than the rated drive current I 0 , and its light emission is dimmed; if p is greater than 1, it means that the laser unit is in the state of overcurrent driving, and its light emission becomes brighter. If p is too large, that is, the ideal driving current I(t) of the laser unit obtained by the signal processing module 11 according to the brightness distribution information of the current image frame is much larger than the rated driving current I 0 of the laser unit. If the ideal driving current I is directly used (t) When driving the laser unit, there may be a risk of COD.
  • the adjusted actual drive current satisfies the following conditions: the actual drive current of the laser unit within the current image frame time is less than or equal to the maximum cut-off of the laser unit. current.
  • the maximum off current of the laser unit is determined by the consumed life of the laser unit and the ratio of the consumed life and the used time of the laser unit.
  • the adjustment module 12 is configured to determine the maximum single-frame life decay rate of the laser unit according to the life data information of the laser unit, and calculate the maximum cut-off current of the laser unit according to the obtained maximum single-frame life decay rate, and adjust the laser based on the maximum cut-off current.
  • the ideal control current I(t) of the unit makes the adjusted actual driving current I'(t) of the laser unit less than or equal to the maximum off current.
  • the adjustment module 12 is configured to calculate the consumed life of the laser unit before the image frame to be displayed is displayed according to the used time of the laser unit, the historical driving current and the historical life decay rate, and based on the used time of the laser unit time, to determine the ratio of the consumed life of the laser unit to the used time, that is, the over-life usage rate O(t 0 ) of the laser unit.
  • the maximum single-frame life decay rate r D of the laser unit within the current image frame time is determined by the consumed life of the laser unit and the The over-life usage rate determines that at the maximum single-frame lifetime decay rate r D , there is a maximum cut-off current of a laser unit.
  • the adjustment module 12 is also used to calculate the maximum cut-off current of the laser unit according to the maximum single-frame life decay rate, and optimize the ideal drive current I(t) based on the maximum cut-off current to obtain the actual drive current I'(t), by The actual driving current of the laser unit is obtained, and the optimization of the ideal driving current I(t) is completed.
  • the optimized actual driving current I'(t) is used to drive the laser unit, so that the lifetime decay rate of the laser unit under the actual driving current during the current image frame time is less than or equal to the laser unit at Maximum single-frame lifetime decay rate driven by maximum off current.
  • the life management module 13 is used to calculate the life consumption information of the laser unit in the current image frame, including: obtaining the actual driving current and actual working temperature of the laser unit in the current image frame, and determining the laser unit in the current image frame.
  • the lifetime consumed by the laser unit to update the lifetime data information of the laser unit. Specifically, the lifespan consumed by the laser unit in the current image frame is subtracted from the remaining lifespan of the laser unit before the current image frame is played to obtain the updated lifespan data information of the laser unit.
  • the life management module 13 calibrates the life of the laser unit to be 100% before the laser unit is put into use, and the life management module 13 is further configured to use the percentage of life consumed by the laser unit in the current image frame as the life consumed by the laser unit, and The lifespan consumed by the laser unit in the current image frame is subtracted from the remaining lifespan of the laser unit before the current image frame is played, so as to obtain the updated lifespan data information of the laser unit.
  • the updated life data information is used to optimize the ideal driving current required by the laser unit when the next image frame is displayed, thereby obtaining the actual driving current of the laser unit when the next image frame is displayed.
  • the working conditions of the laser unit include the driving current value and the working temperature of the laser unit.
  • the projection device can obtain the driving current value according to the actual driving current, and obtain the working temperature of the laser unit according to the temperature sensor.
  • the control device 10 when the display of the current image frame is completed, continues to determine the image frame to be displayed in the next frame according to the image signal to be displayed, and determines that the laser unit required for displaying the next image frame is in the next image frame.
  • the ideal driving current of the frame is determined, and the life data information of the laser unit is re-determined, which is used to optimize the ideal driving current of the laser unit required for displaying the next image frame, thereby obtaining the actual driving current for displaying the next image frame.
  • the life data information of the laser unit includes the design life, the consumed life, the used time, the remaining life, and the ratio of the consumed life to the used time (over-life usage rate) of the laser unit.
  • a timer can be set inside the projection device to record the used time of the laser unit.
  • the control device 10 calculates the image to be displayed by the laser unit according to the used time of the laser unit, historical driving current, historical life decay rate and other historical operating conditions. The elapsed life before the frame is displayed, and the remaining life of the laser unit can be calculated based on the design life of the laser unit.
  • the calculation process of the remaining life of the laser unit can be obtained by the following analysis.
  • the lifetime curve f(I, T) of the laser unit can be used to calculate the consumed lifetime of the laser unit according to the historical operating conditions of the laser unit, so as to determine whether the laser unit can reach the design lifetime index.
  • its consumed life L(t 0 ) can be expressed as:
  • the current remaining life of the laser unit can be determined based on the life that has been consumed by the laser unit during the historical operation, the historical remaining life, and the life that needs to be consumed by the current image frame .
  • the lifetime of the laser unit that has been consumed in the historical operation process should be understood as the lifetime of the laser unit accumulated before the current image frame is displayed; the remaining lifetime of the history should be understood as the laser unit before the current image frame is displayed.
  • the remaining life of the laser unit; the current remaining life of the laser unit should be understood as the remaining life of the laser unit after the current image frame is displayed. Then you can get:
  • the historical remaining life can be determined according to the design life and the consumed life of the laser unit in the historical operation process, wherein the consumed life of the laser unit in the historical operation process can be calculated according to the above calculation formula (6);
  • the lifetime L(t 0 +t f ) that the unit needs to consume in the current image frame time can be obtained by the following formula:
  • t f is the duration for the laser unit to display the current frame.
  • the updated life data information of each laser unit can be obtained, that is, the remaining life of the laser unit:
  • the life management strategy determined by the control device 10 defines that the adjusted actual driving current I′(t) of the laser unit is less than or equal to the maximum off current I max , wherein the maximum off current of the laser unit is determined by the laser unit.
  • the consumed life of the laser unit and the ratio of the consumed life to the used time of the laser unit (over-life usage rate) are determined.
  • the life management strategy defines the life management parameter conditions.
  • the operating parameters of the laser unit should satisfy the life management parameter conditions (for example, In the current image frame time, the actual driving current I'(t) of the laser unit is less than or equal to the maximum cut-off current I max , and the maximum single-frame life decay rate of the laser unit should be less than the maximum single-frame life determined by the preset life management strategy. Attenuation rate threshold), so that the projection equipment can ensure that the actual life of the laser unit is greater than the design life under the premise of improving the display high brightness.
  • control device when the control device optimizes the ideal control current of the laser unit based on the set life management strategy, it can be based on the consumed life L(t 0 ) of the laser unit and the over-life usage rate of the laser unit. O(t 0 ) determines the maximum single-frame lifetime decay rate r D of the laser unit, then the maximum single-frame lifetime decay rate r D of the laser unit can be expressed as:
  • the ideal driving current I(t) of the laser unit is optimized according to the life data information of the laser unit, which can be understood as: under the maximum single-frame life decay rate r D of the laser unit, there is a maximum cut-off current I max , and use the maximum cut-off current I max to cut off the ideal drive current I(t) of the laser unit, so as to obtain the adjusted actual drive current I′(t) of the laser unit as:
  • the maximum cut-off current I max of the laser unit should satisfy the following inequality:
  • L(t 0 +t f ) is the lifespan consumed by the ideal control current I(t) of the laser unit in the current image frame after I max is truncated, and t f is the duration of the current image frame.
  • the life management strategy determined by the control device 10 defines the life management parameter conditions (for example, the maximum single-frame life decay rate r D , the maximum cut-off current I max ).
  • the operating parameters of the laser unit should meet the conditions of life management parameters, that is, the actual driving current I'(t) of the laser unit within the current image frame time is less than or equal to the maximum cut-off current I max , the maximum single-frame lifetime decay rate of the laser unit should be less than the maximum single-frame lifetime decay rate threshold determined by the preset lifetime management strategy, so that the projection equipment can ensure that the actual lifetime of the laser unit meets the Design life requirements.
  • the display of the image signal requires the projection device 100 to always display higher brightness.
  • the maximum single-frame life of the laser unit can be set after the projection device 100 is used for a preset time.
  • the decay rate I max is set to a certain value so that the maximum brightness displayed by the projection apparatus 100 is kept substantially constant.
  • the preset time may be 0, that is, the projection device 100 is a new machine, or it may be used for a certain period of time.
  • the control device 10 adjusts the ideal driving current I(t) of the laser unit based on the constant maximum cut-off current I max .
  • the maximum single-frame life decay rate r of the laser unit D should satisfy the following inequalities:
  • the maximum single-frame lifetime decay rate r D of the laser unit can take a limit value, then the maximum single-frame lifetime decay rate r D of the laser unit can be obtained by the following formula:
  • the display of the image signal does not require the projection device to always display higher brightness, so the actual driving current value actually used to drive the laser unit is usually less than its rated driving current I 0 , at this time the laser unit is The consumed life is shorter than its used time.
  • the actual driving current of the laser unit can be made greater than its rated driving current I 0 , then the maximum single-frame life decay rate of the laser unit r D should be determined based on the current consumed life of the laser unit, that is, based on the remaining life of the laser unit. Assuming that the laser unit has been running for the time L T , in order to ensure that the actual life of the laser unit meets the requirements of the design life L d , the maximum single-frame life decay rate r D of the laser unit should satisfy the following inequality:
  • r real is the actual lifetime decay rate of the laser unit during the time that the laser unit has been operating LT .
  • r D can take a limit value, then in order to ensure that the actual lifetime of the laser unit meets the requirements of the design lifetime L d , the maximum single-frame lifetime of the laser unit
  • the life decay rate r D can be obtained by the following formula:
  • the actual driving current I'(t) of the laser unit should make the actual life of the laser unit greater than the design life.
  • the maximum single-frame life decay rate when the running time reaches the design life and the maximum single-frame life decay rate of the laser unit at the current time are used to determine the maximum single-frame life decay rate of the laser unit.
  • the maximum single-frame life decay rate r D of the laser unit can be expressed as:
  • L T is the used time of the laser unit
  • L d is the design life of the laser unit
  • a is the maximum life decay rate of the laser unit when the use time is LT
  • b is the maximum life of the laser unit when the use time reaches the design life Lifetime decay rate.
  • the service time of the laser unit reaches the design life, its maximum life decay rate has a minimum value, so usually a>b.
  • the greater than or equal sign in the inequality (16) can be replaced with the equal sign to calculate the maximum value of the maximum lifetime decay rate a when the operating time of the laser unit reaches the current time LT , that is, the operating time of the laser unit
  • the maximum value of the maximum life decay rate a when reaching the current time L T can be obtained by the following formula:
  • b in the inequality (16) represents the limit condition of the maximum output brightness of the laser unit when the operating time of the laser unit reaches the design life, and the value of b can be set according to the application requirements and standard limitations of the actual projection equipment. For example, according to the industry specification of laser display, when the operating time of the laser unit reaches the design life, the display brightness attenuation of the laser unit should not exceed 50%. Therefore, the value of b can be taken as 0.5. Therefore, when b is known, the value of the maximum lifetime decay rate a when the operating time of the entire laser unit reaches the current time L T can be determined by calculating formula (17), and then the current image can be obtained according to formula (15). The maximum single-frame lifetime decay rate r D of the laser unit within the frame time.
  • the historical life decay rate of the laser unit can be calculated according to the historical working conditions, and the projection equipment can be calculated according to the used time, historical driving current and historical life of the laser unit.
  • rate calculate the consumed life of the laser unit before the image frame to be displayed is displayed, from which the remaining life of the laser unit can be obtained, and calculate the maximum single-frame life decay rate r D , according to the maximum single-frame life decay rate r D
  • magnification p so as to complete the optimization of the ideal driving current I(t) of the laser unit.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Projection Apparatus (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)

Abstract

本发明实施例公开了一种投影设备，包括光源装置、空间光调制器和控制装置；光源装置包括至少一个激光单元；控制装置用于根据待显示的图像信号获取当前图像帧的亮度分布信息，并根据当前图像帧的亮度分布信息以及激光单元的寿命数据信息控制激光单元的驱动电流，使其驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流；空间光调制器设置在光源装置出射的光的光路上，用于对光源装置出射的光进行调制，得到调制图像。上述的投影设备能够充分利用激光单元的寿命与驱动电流的关系，能够保证光源装置在满足寿命要求的情况下实现高亮度的显示。

Description

投影设备 技术领域
本发明涉及投影显示技术领域，更具体地，涉及一种投影设备。
背景技术
随着显示技术的发展，投影设备的应用越来越广泛，包括教育投影机、家庭投影机和工程投影机等，投影技术给人们的生活、学习及工作带来了极大的改变。人们对投影设备显示质量的需求不断提高，对高亮度显示的需求也与日俱增。高动态范围(HDR)的投影系统能够增加投影机输出的对比度和峰值亮度，使得画面中的亮场和暗场部分都能显示丰富的灰阶信息从而大大提高画面的效果和观众的观影体验，HDR技术正在成为投影显示领域研究的重点。
目前，实现HDR投影系统的一种方案为采用LCD背光的Local Dimming(区域调光)技术。该技术方案采用激光器阵列作为投影设备的光源，每颗激光器负责一个区域的照明，在投影显示时，根据投影画面各个区域的亮度来动态的控制每颗激光器光源的发光强度，以实现高对比度显示。然而，由于投影画面亮度在空间上的不平衡，则照射不同区域的激光器衰减不同，因而播放一段时间画面后不同区域的激光器剩余寿命不同。因此，如何平衡光源的亮度以及寿命是个亟待解决的问题。
发明内容
本发明实施例提供了一种投影设备，以改善上述问题。
本发明实施例提供了一种投影设备，包括光源装置、空间光调制器和控制装置；光源装置包括至少一个激光单元；控制装置用于根据待显示的图像信号获取当前图像帧的亮度分布信息，并根据当前图像帧的亮度分布信息以及激光单元的寿命数据信息 调整激光单元的驱动电流，使调整后的实际驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流；空间光调制器设置在光源装置出射的光的光路上，用于对光源装置出射的光进行调制，得到调制图像。
进一步地，控制装置用于根据当前图像帧的亮度分布信息，确定激光单元的理想驱动电流，并根据激光单元的寿命数据信息调整激光单元的理想驱动电流，以得到实际驱动电流。
进一步地，激光单元的寿命数据信息包括激光单元的已消耗寿命和已使用时间，当激光单元的已消耗寿命小于已使用时间时，控制装置调整激光单元的驱动电流，使调整后的实际驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流。
进一步地，在当前图像帧时间内激光单元的实际驱动电流小于或等于激光单元的最大截止电流。
进一步地，激光单元的最大截止电流由激光单元的已消耗寿命、激光单元的已消耗寿命与已使用时间的比值确定。
进一步地，在当前图像帧时间内激光单元在实际驱动电流下的寿命衰减速率小于或等于激光单元在最大截止电流驱动下的最大单帧寿命衰减速率。
进一步地，在使用预设时间后激光单元的最大单帧寿命衰减速率为一定值。
进一步地，在当前图像帧时间内激光单元的最大单帧寿命衰减速率由激光单元的当前使用时间的最大寿命消耗速率和激光单元设计寿命到达时的最大寿命消耗速率确定。
进一步地，在当前图像帧时间内激光单元的最大单帧寿命衰减速率为r D：
Figure PCTCN2021116379-appb-000001
其中：L T为激光单元的已使用时间，L d为激光单元的设计寿命，a为激光单元使用时间为L T时的最大寿命衰减速率，b为激光单元的使用时间达到设计寿命时的最大寿命衰减速率。
进一步地，控制装置还用于计算在当前图像帧时间内激光单元的寿命消耗信息，以更新激光单元的寿命数据信息。
进一步地，控制装置用于计算当前图像帧内激光单元所消耗的寿命；以及将激光单元的在当前图像帧播放前的剩余寿命减去当前图像帧内该激光单元所消耗的寿命，得到激光单元更新后的寿命数据信息。
本发明实施例提供的投影设备中，光源装置包括至少一个激光单元，在显示每一帧图像画面时，控制装置根据当前图像帧的亮度分布信息以及激光单元的寿命数据信息调整激光单元的驱动电流，使调整后的实际驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流，以使激光单元输出高亮度的光以供空间光调制器进行调制，该方案通过根据待显示画面的亮度以及激光单元的寿命确定激光单元的驱动电流，充分利用了激光单元的寿命与驱动电流的关系，使得激光单元在超过其额定驱动电流工况下间歇的工作从而输出更高峰值亮度的光的同时又不影响系统的使用寿命，能够保证光源装置在满足寿命要求的情况下实现高亮度的显示。
附图说明
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。
图1示出了本发明实施例请提出的一种投影设备的模块框图。
图2示出了本发明实施例请提出的投影设备的控制装置的功能模块示意图。
图3示出了本发明实施例提出的一种投影设备的工作流程图。
具体实施方式
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。下面将结合附图以及具体实施例对本发明提供的投影设备作出详细介绍。
请参见图1，图1示出了本发明实施例提供的投影设备100的模块框图，该投影设备100可以是但不限于激光电视、教育投影仪、微投、影院投影机等具备投影功能的设备，也可以是连接具备投影功能的设备，并利用该设备的测距传感器的计算机系统，例如连接投影设备的个人电脑、笔记本电脑、平板、智能手机等。需要说明的是，本申请实施例中的投影设备的投影方向不作限定，其可以是背投或前投。
投影设备100包括控制装置10、光源装置30和空间光调制器40。光源装置30包括至少一个激光单元；控制装置10用于根据待显示的图像信号获取当前图像帧的亮度分布信息，并根据当前图像帧的亮度分布信息以及激光单元的寿命数据信息调整激光单元的驱动电流，使调整后的实际驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流；空间光调制器40设置在光源装置30出射的光的光路上，用于对光源装置30出射的光进行调制，得到调制图像。
上述的投影设备100中，光源装置30包括至少一个激光单元，在显示每一帧图像画面时，控制装置10根据当前图像帧的亮度分布信息以及激光单元的寿命数据信息调整激光单元的驱动电流，使调整后的实际驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流，以使激光单元输出高亮度的光以供空间光调制器40进行调制，该方案通过根据待显示画面的亮度以及激光单元的寿命确定激光单元的驱动电流，充分利用了激光单元的寿命与驱动电流的关系，使得激光单元在超过其额定驱动电流工况下间歇的工作从而输出更高峰值亮度的光的同时又不影响投影设备100的使用寿命，能够保证光源装置30在满足寿命要求的情况下实现高亮度的显示。
在一些实施例中，投影设备100还包括光源驱动器以及成像元件。光源驱动器分别与控制装置10和光源装置30连接，控制装置10用于接收待显示的图像信号，并根据待显示的图像信号生成控制信号，光源驱动器用于接收控制装置10发送的控制信号，并根据控制电流输出驱动光源装置30的驱动电流，以点亮光源装置30，其中，光源驱动器根据控制信号调整输入到光源装置30的驱动电流以驱动光源装置30。对于加入了光源动态调制技术的投影设备100，光源装置30的驱动电流是随显示画面的内容变化的。光源装置30用于发出光源光，空间光调制器40用于根据图像信号调制光源装置30发出的光源光以产生 具有调制图像的图像光。成像元件用于接收空间光调制器40产生的图像光并将图像光投影至预定位置或预定元件(如投影屏幕或墙壁等)来显示投影图像。
下文将对本申请提供的投影设备100的控制装置10进行详细介绍。
请参阅图2，控制装置10可以包括信号处理模块11、调整模块12以及寿命管理模块13，其中，寿命管理模块13包括储存单元，用于储存激光单元的寿命数据信息。信号处理模块11用于根据待显示的图像信号获取当前图像帧的亮度分布信息，并根据当前图像帧的亮度分布信息确述激光单元的理想驱动电流，调整模块12根据激光单元的寿命数据信息调整激光单元的理想驱动电流，得到调整后的激光单元的实际驱动电流，激光单元在该实际驱动电流的驱动下发光，以使激光单元输出目标亮度的光。寿命管理模块13用于计算在当前图像帧内激光单元的寿命消耗信息，以更新激光单元的寿命数据信息。上述各模块可以为运行于计算机可读存储介质中的程序模块，上述各个模块的用途及工作具体如下：
信号处理模块11用于根据待显示的图像信号获取当前图像帧的亮度分布信息，并根据当前图像帧的亮度分布信息确述激光单元的理想驱动电流。待显示的图像信号可以被存储于投影设备本地，也可以为投影设备基于数据连接(如局域网数据连接或广域网数据连接等)所接收的图像信号。其中，该图像信号可以来自于先存储(例如，预先将需要投影的音视频数据拷贝至投影设备中存储)或者是即时存储(例如，将存储有需要投影的音视频数据的移动硬盘插在投影设备上)的图像内容，具体存储方式不作限定；图像内容可以为视频文件中的图像内容、图片文件中的图像内容等，本申请实施例对此不进行限制。
在本申请实施例中，投影设备可以根据自身的类型以及待显示的图像信号，统计当前图像帧画面的亮度分布。作为一种实施例，投影设备可以为基于global dimming技术的投影设备，则只需要统计整个画面的亮度最大值。而采用local dimming的投影设备，则需要分区域地统计各个区域的最大亮度。采用动态色域技术的投影设备，则需要统计整个画面中不同基色光的亮度最大值。采用扫描光源的投影设备，需要将二维画面的亮度分布变成扫描路径上的亮度变化曲线。
信号处理模块11在获取到当前图像帧的亮度分布信息后，基于当前图像帧的亮度 分布信息生成激光单元的理想驱动电流I(t)，该理想驱动电流I(t)表征对应激光单元输出光的理想亮度。激光单元的理想驱动电流I(t)可以理解为，未考虑激光单元的实际工况以及寿命数据信息时的驱动电流。信号处理模块11基于当前图像帧画面的亮度分布(亮度曲线)，确定当前图像帧显示时所需的激光单元的理想驱动电流I(t)。
调整模块12根据激光单元的寿命数据信息调整激光单元的理想驱动电流I(t)，以得到实际驱动电流I’(t)，其中，激光单元的实际驱动电流I’(t)表征对应激光单元输出光的实际亮度。该实际驱动电流I’(t)在当前图像帧时间内的至少部分时段大于额定驱动电流，即在当前图像帧时间内的至少部分时段激光单元处于过流驱动状态，使得激光发出更高亮度的光，从而满足HDR对光源装置的亮度要求。
在本申请实施例中，空间光调制器40包括但不限于数字微镜器件(Digital Micro-mirror Device，DMD)，还可为液晶显示面板(Liquid Crystal Display，LCD)或硅基液晶(Liquid Crystal on Silicon，LCOS)。为了方便说明，空间光调制器40采用数字微镜器件进行举例，但这并不用于限定本发明的范围。空间光调制器40包括多个微镜单元，每个微镜单元对应调制图像的一个像素，当微镜单元为“开”状态时，该微镜单元反射光源光至对应的像素区域，对应的像素为“亮”状态，当微镜单元为“关”状态时，该微镜单元不反射光源光至对应的像素区域，对应的像素为“暗”状态。光源装置30出射的光照射在空间光调制器40上，空间光调制器40根据待显示的图像信号对光源装置30出射的光进行调制，当前图像帧时间内，调整模块12根据激光单元的寿命数据信息调整激光单元的理想驱动电流I(t)，使调整后的实际驱动电流I’(t)在当前图像帧时间内的至少部分时段大于额定驱动电流，相较于连续恒定电流驱动时，光源装置30以电流过冲的方式工作时其出射的光的亮度能够提高。
具体地，当前图像帧时间包括多个位平面调制时段(例如8位或10位)，调整模块12根据激光单元的寿命数据信息调整激光单元的理想驱动电流I(t)，使调整后的实际驱动电流I’(t)在当前图像帧时间内的至少一个位平面调制时段大于额定驱动电流。若激光单元驱动电流为额定驱动电流时，激光单元的发光亮度为L，则在该至少一个位平面调制时段内，激光单元的实际驱动电流I’(t)大于额定驱动电流，此时激光单元 的发光亮度可达到ML(M>1)，以使在该至少一个位平面调制时段内光源装置30的发光亮度提高，使调制图像的各像素达到预设的灰阶值。
在本申请实施例中，控制装置10根据激光单元的寿命数据信息，确定激光单元对应的寿命管理策略(也即本申请提供的对理想控制电流的优化过程)，使得激光单元输出更高峰值亮度的光的同时又不影响系统的使用寿命。具体地，激光单元的寿命数据信息用于表征能够影响激光单元实际寿命的因素，激光单元的寿命数据信息包括激光单元的已消耗寿命和已使用时间。
无论是何种激光投影设备，在使用一段时间后，必定导致激光单元寿命的衰减，也即导致激光单元的剩余寿命减少。而激光单元已经消耗的寿命，可以由激光投影设备的显示原理、激光单元的实际工况确定。例如，普通的激光投影设备中，激光单元是恒定电流工作的，因此，激光单元的寿命衰减速率是一个恒定值。而采用了global dimming技术的激光投影设备，激光单元会根据画面中的最大亮度决定激光单元的输出，因而激光单元的寿命衰减速率是一个随着工况变化的值，但是由于global dimming技术中所有激光单元都是统一变化的，因此每个激光单元的寿命衰减速率是一样的。如果采用了动态色域技术(HDC技术)的激光投影设备，不同基色光的激光光单元(如产生荧光的蓝激光，作为色彩补偿的红、绿激光等)，将会根据画面的内容产生不同的调制曲线，因而不同基色光的激光单元具有不同的寿命衰减速率。而采用Local dimming技术的激光投影设备，由于画面亮度在空间上的不平衡，则照射不同区域的激光单元不同的基色光激光单元不同，因而播放一段时间画面后不同区域的激光单元剩余寿命不同。
光学灾变损伤(COD)是影响激光单元寿命的最主要的因素，高电流驱动下激光单元的寿命主要由COD决定。在考虑COD和激光单元正常的材料衰减等其他寿命影响因素的情况下，激光单元的寿命L可以表示为：
Figure PCTCN2021116379-appb-000002
其中：I为激光单元的连续恒定驱动电流，T为激光单元的工作温度，I、T用于表征激光单元在实际运行时的工况。当激光单元的驱动电流I大于该温度下的COD阈值电流I th(T)时，就会发生COD，因而在这种电流下激光单元寿命是0。而当激光单元的驱动电 流I小于该阈值电流I th(T)时，激光单元不会发生COD。在这种环境和工况下，激光单元的寿命L可以表示为电流和温度的函数(也即上式(1))。这个函数的值随驱动电流的升高而减小，意味着越大的驱动电流激光单元的寿命越短。激光单元的固有寿命曲线f(I,T)可以理解为激光单元的固有特性，其可以预置在投影设备内(例如预先存储在投影设备的存储器内)，也可以通过激光单元老化测试得出。
假设激光单元的设计寿命是L d，则单位时间内在工况(驱动电流I和工作温度T)下激光单元消耗的寿命r(I,T)可以表示为：
Figure PCTCN2021116379-appb-000003
激光单元在已使用时间t 0后，其已经消耗的寿命L(t 0)可以表示为：
Figure PCTCN2021116379-appb-000004
则可以定义激光单元的超寿命使用率O(t 0)为：
Figure PCTCN2021116379-appb-000005
O(t 0)大于1表示激光单元在已使用时间t 0过程中的实际工况超过了设计寿命时设计的工况，后续若没有改变激光单元的实际寿命会短于设计寿命。而O(t 0)小于1则表示激光单元在已使用时间t 0过程中的实际工况没有超过设计寿命时设计的工况，若后续没有改变则激光单元的实际寿命会长于或等于设计寿命。因此，对于O(t 0)小于1的激光单元，提高其驱动电流，使其在过流驱动下工作，也即当激光单元的已消耗寿命小于已使用时间时，控制装置10调整激光单元的驱动电流，使调整后的实际驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流，从而实现输出最大亮度与满足设计寿命之间的平衡。
由于在高电流驱动下激光单元的寿命主要由COD决定，因此，对于过流驱动的激光单元，为了防止激光单元发生COD，需要对其驱动电流的上限做出限制。
进一步地，信号处理模块11基于激光单元的理想控制电流I(t)以及额定驱动电流I 0， 确定激光单元的过流驱动倍率p。激光单元的过流驱动倍率p由激光单元的理想控制电流I(t)与激光单元的额定驱动电流I 0的比值表示，即激光单元的过流驱动倍率p可以表示为：
Figure PCTCN2021116379-appb-000006
p小于1表示激光单元的驱动电流小于额定驱动电流I 0，其发光减暗，p大于1表示激光单元处在过流驱动的状态，其发光变亮。若p过大，也即信号处理模块11根据当前图像帧的亮度分布信息获得的激光单元的理想驱动电流I(t)远大于激光单元的额定驱动电流I 0，如果直接用该理想驱动电流I(t)驱动激光单元，则可能有发生COD的风险。
为避免激光单元发生COD，控制装置10在调整激光单元的驱动电流时，使调整后的实际驱动电流满足以下条件：在当前图像帧时间内激光单元的实际驱动电流小于或等于激光单元的最大截止电流。其中，激光单元的最大截止电流由激光单元的已消耗寿命、激光单元的已消耗寿命与已使用时间的比值确定。
进一步地，调整模块12用于根据激光单元的寿命数据信息确定激光单元的最大单帧寿命衰减速率，并根据获得的最大单帧寿命衰减速率计算激光单元的最大截止电流，基于最大截止电流调整激光单元的理想控制电流I(t)，使得调整后的激光单元的实际驱动电流I’(t)小于或等于最大截止电流。
具体而言，调整模块12用于根据激光单元的已使用时间、历史驱动电流以及历史寿命衰减速率，计算激光单元在待显示的图像帧被显示之前的已消耗寿命，并基于激光单元的已使用时间，确定激光单元的已消耗寿命与已使用时间的比值，即激光单元的超寿命使用率O(t 0)。不管对激光单元采用何种寿命管理策略(对理想控制电流的优化过程)，激光单元在当前图像帧时间内的最大单帧寿命衰减速率r D都是由激光单元的已消耗寿命以及激光单元的超寿命使用率决定，在该最大单帧寿命衰减速率r D下，存在着一个激光单元的最大截止电流。进一步地，调整模块12还用于根据最大单帧寿命衰减速率计算激光单元的最大截止电流，基于该最大截止电流去优化理想驱动电流I(t)从而得到实际驱动电流I’(t)，由此得到激光单元的实际驱动电流，则完成了理想驱动电流I(t)的优化。在本实施例中，采用经优化得出的实际驱动电流I’(t)来驱动激光单元，能够使得在当前图像帧时间内激光单元在实际驱动电流下的寿命衰减速率小于或等于激光单元在最大截止电流驱动下的 最大单帧寿命衰减速率。
在本申请实施例中，寿命管理模块13用于计算在当前图像帧内激光单元的寿命消耗信息，包括：获取当前图像帧内激光单元的实际驱动电流以及实际工作温度，确定在当前图像帧内激光单元消耗的寿命，以更新激光单元的寿命数据信息。具体地，将激光单元的在当前图像帧播放前的剩余寿命减去当前图像帧内该激光单元所消耗的寿命，得到激光单元更新后的寿命数据信息。例如，寿命管理模块13在激光单元投入使用前标定该激光单元的寿命为100％，寿命管理模块13还用于将当前图像帧内激光单元消耗的寿命百分比作为该激光单元所消耗的寿命，并将该激光单元的在当前图像帧播放前的剩余寿命减去当前图像帧内该激光单元所消耗的寿命，从而得到该激光单元更新后的寿命数据信息。
在本申请实施例中，更新后的寿命数据信息用于优化下一图像帧显示时激光单元所需的理想驱动电流，进而得到下一图像帧显示时激光单元的实际驱动电流。在本申请实施例中，激光单元的工况包括驱动电流值以及激光单元的工作温度。在当前图像帧被显示时，投影设备可以根据实际驱动电流获取驱动电流值，并根据温度传感器获取激光单元的工作温度。
在一些实施方式中，在当前图像帧显示完毕时，控制装置10继续根据待显示的图像信号，确定下一帧待显示的图像帧，并确定下一图像帧显示时所需的激光单元在下一帧的理想驱动电流，且重新确定激光单元的寿命数据信息，其用于优化下一图像帧显示时所需的激光单元理想驱动电流，进而得到下一图像帧显示时的实际驱动电流。
请参阅图3，下文将结合参数计算的流程图，对上述的各参数的计算进行详细说明。
(一)激光单元的寿命数据信息
本申请实施例中，激光单元的寿命数据信息包括激光单元的设计寿命、已消耗寿命、已使用时间、剩余寿命、以及已消耗寿命与已使用时间的比值(超寿命使用率)等。投影设备的内部可以设置计时器，记录激光单元的已使用时间，控制装置10根据激光单元的已使用时间、历史驱动电流以及历史寿命衰减速率等历史运行工况，计算激光单元在待显示的图像帧被显示之前的已消耗寿命，并基于激光单元的设计寿命可计算得出激光单元的 剩余寿命。激光单元的剩余寿命的计算过程，可以由以下分析得出。
作为一种实施方式，可以利用激光单元的寿命曲线f(I,T)，根据激光单元的历史运行工况来计算激光单元的已经消耗的寿命，从而确定激光单元是否能够达到设计寿命指标。根据上述的计算式(2)，在激光单元工作t 0时间后，其已经消耗寿命L(t 0)可以表示为：
Figure PCTCN2021116379-appb-000007
在本实施例中，对于正在运行播放图像内容的投影设备，可以基于激光单元在历史运行过程中已经消耗的寿命、历史的剩余寿命以及当前图像帧所需消耗的寿命确定激光单元的当前剩余寿命。具体而言，激光单元在历史运行过程中已经消耗的寿命，应理解为激光单元在当前图像帧被显示之前累计消耗的寿命；历史的剩余寿命，应理解为激光单元在当前图像帧被显示之前的剩余寿命；激光单元的当前剩余寿命，应理解为激光单元在当前图像帧被显示之后的剩余寿命。那么可得：
激光单元的当前剩余寿命(简称为剩余寿命)＝历史的剩余寿命-当前图像帧时间内该激光单元所消耗的寿命。
而历史的剩余寿命，则可以根据设计寿命以及激光单元在历史运行过程中已消耗寿命确定，其中，激光单元在历史运行过程中已消耗寿命可根据上述的计算式(6)计算得出；激光单元在当前图像帧时间内所需消耗的寿命L(t 0+t f)可以由以下计算式得出：
Figure PCTCN2021116379-appb-000008
其中，t f为激光单元显示当前帧的持续时间。
根据上述的计算式(6)和(7)，可得每个激光单元更新后的寿命数据信息，也即激光单元的剩余寿命：
L d＝L d-L(t 0)-L(t 0+t f)。
(二)最大截止电流
在本申请实施例中，控制装置10所确定的寿命管理策略限定激光单元调整后的实际 驱动电流I’(t)小于或等于最大截止电流I max，其中，激光单元的最大截止电流由激光单元的已消耗寿命、激光单元的已消耗寿命与已使用时间的比值(超寿命使用率)确定。
作为一种实施方式，寿命管理策略定义了寿命管理参数条件，当控制装置10根据预设的寿命管理策略优化激光单元的理想控制电流时，激光单元的运行参数应当满足寿命管理参数条件(例如，在当前图像帧时间内激光单元的实际驱动电流I’(t)小于或等于最大截止电流I max、激光单元的最大单帧寿命衰减速率应小于预设的寿命管理策略所确定的最大单帧寿命衰减速率阈值)，以使投影设备在提高显示高亮度的前提下，保证激光单元实际寿命大于设计寿命。
进一步地，在一些具体的实施例中，控制装置基于设定的寿命管理策略优化激光单元的理想控制电流时，可以根据激光单元已消耗的寿命L(t 0)以及激光单元的超寿命使用率O(t 0)确定激光单元的最大单帧寿命衰减速率r D，则激光单元的最大单帧寿命衰减速率r D可以表示为：
r D＝r D(L(t 0))。
基于上述的分析，根据激光单元的寿命数据信息优化激光单元的理想驱动电流I(t)，可以理解为：在激光单元的最大单帧寿命衰减速率r D可下，存在一个最大截止电流I max，并用该最大截止电流I max去截断激光单元的理想驱动电流I(t)，从而得到调整后的激光单元的实际驱动电流I′(t)为：
Figure PCTCN2021116379-appb-000009
若要满足“激光单元在实际驱动电流下的寿命衰减速率小于或等于激光单元在最大截止电流驱动下的最大单帧寿命衰减速率”的寿命管理参数条件，激光单元最大截止电流I max应满足以下不等式：
Figure PCTCN2021116379-appb-000010
其中，L(t 0+t f)为当前图像帧时间内激光单元的理想控制电流I(t)在做了I max截断后所消耗的寿命，t f为当前图像帧的持续时间。则有：
Figure PCTCN2021116379-appb-000011
因此，在激光单元的实际驱动电流I′(t)的计算过程中，存在一个最大截止电流I max，满足上面的不等式。根据最大截止电流I max调整激光单元的理想驱动电流I(t)，依据上式(8)可得调整后的激光单元的实际驱动电流I′(t)，并使实际驱动电流I′(t)小于或等于最大截止电流I max，所以，基于上式(8)、(9)和(10)，即可对激光单元的理想驱动电流I(t)进行优化，得的调整后的激光单元的实际驱动电流I′(t)。
(三)最大单帧寿命衰减速率
下面将对最大单帧寿命衰减速率的计算过程进行举例说明。
由以上推导可知，作为一种实施方式，控制装置10所确定的寿命管理策略定义了寿命管理参数条件(例如最大单帧寿命衰减速率r D、最大截止电流I max)，当根据寿命管理策略优化激光单元的理想驱动电流I(t)时，激光单元的运行参数应当满足寿命管理参数条件，也即，在当前图像帧时间内激光单元的实际驱动电流I’(t)小于或等于最大截止电流I max、激光单元的最大单帧寿命衰减速率应小于预设的寿命管理策略所确定的最大单帧寿命衰减速率阈值，以使投影设备在提高显示高亮度的前提下，保证激光单元实际寿命满足设计寿命的要求。
在一些实际的使用场景中，图像信号的显示需要投影设备100始终显示较高亮度，作为一种激光单元的寿命管理策略，可以在投影设备100使用预设时间后将激光单元的最大单帧寿命衰减速率I max设置为一定值，从而使投影设备100显示的最大亮度基本保持恒定。其中，预设时间可以为0，即投影设备100为新机，也可以为使用一定的时间后。控制装置10基于该恒定的最大截止电流I max来调整激光单元的理想驱动电流I(t)，为保证激光单元的实际寿命满足设计寿命L d的要求，激光单元的最大单帧寿命衰减速率r D应满足以下不等式：
Figure PCTCN2021116379-appb-000012
基于上述不等式(11)，在确定激光单元的最大单帧寿命衰减速率r D时，r D可以取极限值，则激光单元的最大单帧寿命衰减速率r D可以由以下计算式得出：
Figure PCTCN2021116379-appb-000013
又如，在一些实际的使用场景中，图像信号的显示不需要投影设备始终显示较高亮度，则实际用于驱动激光单元的实际驱动电流值通常小于其额定驱动电流I 0，此时激光单元的已消耗寿命小于其已使用时间，后续的时间里当投影设备需要高亮度时，可以使激光单元的实际驱动电流大于其额定驱动电流动电流I 0，则激光单元的最大单帧寿命衰减速率r D应基于激光单元当前已消耗寿命来确定，也即基于激光单元的剩余寿命来确定。假设激光单元已经运行L T的时间，则为保证激光单元的实际寿命满足设计寿命L d的要求，则激光单元的最大单帧寿命衰减速率r D应满足以下不等式：
Figure PCTCN2021116379-appb-000014
其中，r real为在激光单元已经运行L T的时间内激光单元的实际寿命衰减速率。
基于不等式(13)，在确定激光单元的最大单帧寿命衰减速率r D时，r D可以取极限值，则为保证激光单元的实际寿命满足设计寿命L d的要求，激光单元的最大单帧寿命衰减速率r D可以由以下计算式得出：
Figure PCTCN2021116379-appb-000015
再如，在一些实际的使用场景中，激光单元的实际驱动电流I’(t)应使激光单元的实际寿命大于设计寿命，若激光单元的已消耗寿命大于已运行时间，则可以根据激光单元运行时间到达设计寿命时的最大单帧寿命衰减速率以及激光单元的当前时间的最大单帧寿命衰减速率，来确定激光单元的最大单帧寿命衰减速率。具体而言，假设激光单元已经运行到达当前L T的时间，根据该优化的寿命管理策略，则激光单元的最大单帧寿命衰减速率r D可以表示为：
Figure PCTCN2021116379-appb-000016
其中：L T为激光单元的已使用时间，L d为激光单元的设计寿命，a为激光单元使用时间为L T时的最大寿命衰减速率，b为激光单元的使用时间达到设计寿命时的最大寿命衰减速率。通常情况下，激光单元的使用时间达到设计寿命时其最大寿命衰减速率具有最小值，因此通常a>b。
将上述的计算式(15)带入上述的不等式(14)，可得不等式：
Figure PCTCN2021116379-appb-000017
其中，
Figure PCTCN2021116379-appb-000018
为激光单元的历史寿命衰减速率的平均值。
作为一种实施例，可以将不等式(16)中的大于等于符号替换为等于符号来计算激光单元运行时间达到当前时间L T时的最大寿命衰减速率a的最大值，也即，激光单元运行时间达到当前时间L T时的最大寿命衰减速率a的最大取值可以由以下计算式得出：
Figure PCTCN2021116379-appb-000019
由上文推导可知，不等式(16)中的b表征激光单元运行时间到达设计寿命时激光单元的输出最大亮度限制条件，可以根据实际投影设备的应用需求和标准限制来设定b的取值。例如，根据激光显示的行业规范，通常情况下激光单元运行时间到达设计寿命时，激光单元的显示亮度衰减不应超过50％，因此，b的取值可以取为0.5。因此，在b为已知的情况下通过计算式(17)能够确定整激光单元运行时间达到当前时间L T时的最大寿命衰减速率a的值，进而根据计算式(15)可得到在当前图像帧时间内激光单元的最大单帧寿命衰减速率r D。
综上，在待显示的图像帧被显示之前，激光单元的历史寿命衰减速率是可以根据历史工况条件计算得知的，投影设备可以根据激光单元的已使用时间、历史驱动电流以及历史寿命衰减速率，计算激光单元在待显示的图像帧被显示之前的已消耗寿命，由此可得激光单元的剩余寿命，并计算出最大单帧寿命衰减速率r D，根据最大单帧寿命衰减速率r D计算激光单元的最大截止电流I max，基于该最大截止电流I max去优化理想控制电流I(t)，从而得到激光单元的实际控制电流I′(t)，也可以得到激光单元的过流驱动倍率p，从而完成激光单元理想驱动电流I(t)的优化。
需要说明的是，上面结合附图对本发明的实施例进行了描述，但是本发明并不局限于上述的具体实施方式，上述的具体实施方式仅仅是示意性的，而不是限制性的，本领域的普通技术人员在本发明的启示下，在不脱离本发明宗旨和权利要求所保护的范围情况下，还可做出很多形式，均属于本发明的保护之内。

Claims (11)

  1. 一种投影设备，其特征在于：包括光源装置、空间光调制器和控制装置；
    所述光源装置包括至少一个激光单元；
    所述控制装置用于根据待显示的图像信号获取当前图像帧的亮度分布信息，并根据当前图像帧的亮度分布信息以及所述激光单元的寿命数据信息调整所述激光单元的驱动电流，使调整后的实际驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流；
    所述空间光调制器设置在所述光源装置出射的光的光路上，用于对所述光源装置出射的光进行调制，得到调制图像。
  2. 如权利要求1所述的投影设备，其特征在于，所述控制装置用于根据当前图像帧的亮度分布信息，确定所述激光单元的理想驱动电流，并根据所述激光单元的寿命数据信息调整所述激光单元的理想驱动电流，以得到所述实际驱动电流。
  3. 如权利要求1至2任一项所述的投影设备，其特征在于，所述激光单元的寿命数据信息包括所述激光单元的已消耗寿命和已使用时间，当所述激光单元的已消耗寿命小于已使用时间时，所述控制装置调整所述激光单元的驱动电流，使调整后的实际驱动电流在当前图像帧时间内的至少部分时段大于额定驱动电流。
  4. 如权利要求3所述的投影设备，其特征在于，在当前图像帧时间内所述激光单元的实际驱动电流小于或等于所述激光单元的最大截止电流。
  5. 如权利要求4所述的投影设备，其特征在于，所述激光单元的最大截止电流由所述激光单元的已消耗寿命、所述激光单元的已消耗寿命与已使用时间的比值确定。
  6. 如权利要求4所述的投影设备，其特征在于，在当前图像帧时间内所述激光单元在实际驱动电流下的寿命衰减速率小于或等于所述激光单元在最大截止电流驱动下的最大单帧寿命衰减速率。
  7. 如权利要求6所述的投影设备，其特征在于，在使用预设时间后所述激光单元的最大单帧寿命衰减速率为一定值。
  8. 如权利要求6所述的投影设备，其特征在于，在当前图像帧时间内所述激光单 元的最大单帧寿命衰减速率由所述激光单元的当前使用时间的最大寿命消耗速率和所述激光单元设计寿命到达时的最大寿命消耗速率确定。
  9. 如权利要求8所述的投影设备，其特征在于，在当前图像帧时间内所述激光单元的最大单帧寿命衰减速率为r D：
    Figure PCTCN2021116379-appb-100001
    其中：L T为所述激光单元的已使用时间，L d为所述激光单元的设计寿命，a为所述激光单元使用时间为L T时的最大寿命衰减速率，b为所述激光单元的使用时间达到设计寿命时的最大寿命衰减速率。
  10. 如权利要求1所述的投影设备，其特征在于，所述控制装置还用于计算在当前图像帧时间内所述激光单元的寿命消耗信息，以更新所述激光单元的寿命数据信息。
  11. 如权利要求10所述的投影设备，其特征在于，所述控制装置用于计算当前图像帧内所述激光单元所消耗的寿命；以及将所述激光单元的在当前图像帧播放前的剩余寿命减去当前图像帧内该激光单元所消耗的寿命，得到所述激光单元更新后的寿命数据信息。
PCT/CN2021/116379 2020-09-11 2021-09-03 投影设备 WO2022052867A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202010955040.7A CN114173100A (zh) 2020-09-11 2020-09-11 投影设备
CN202010955040.7 2020-09-11

Publications (1)

Publication Number Publication Date
WO2022052867A1 true WO2022052867A1 (zh) 2022-03-17

Family

ID=80476032

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/116379 WO2022052867A1 (zh) 2020-09-11 2021-09-03 投影设备

Country Status (2)

Country Link
CN (1) CN114173100A (zh)
WO (1) WO2022052867A1 (zh)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050128436A1 (en) * 2003-12-16 2005-06-16 Olympus Corporation Illumination apparatus and image projection apparatus using the illumination apparatus
CN103822116A (zh) * 2013-12-31 2014-05-28 苏州佳世达光电有限公司 光源模组及发光控制方法
CN111176064A (zh) * 2020-03-09 2020-05-19 青岛海信激光显示股份有限公司 激光投影设备
WO2020135293A1 (zh) * 2018-12-29 2020-07-02 深圳光峰科技股份有限公司 一种显示系统

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050128436A1 (en) * 2003-12-16 2005-06-16 Olympus Corporation Illumination apparatus and image projection apparatus using the illumination apparatus
CN103822116A (zh) * 2013-12-31 2014-05-28 苏州佳世达光电有限公司 光源模组及发光控制方法
WO2020135293A1 (zh) * 2018-12-29 2020-07-02 深圳光峰科技股份有限公司 一种显示系统
CN111176064A (zh) * 2020-03-09 2020-05-19 青岛海信激光显示股份有限公司 激光投影设备

Also Published As

Publication number Publication date
CN114173100A (zh) 2022-03-11

Similar Documents

Publication Publication Date Title
CN1841487B (zh) 图像显示装置及图像显示方法
CN100401147C (zh) 图像显示装置、图像显示方法
US7683857B2 (en) Illuminator, projection display device and method for driving the same
JP4111238B2 (ja) 画像表示装置
JP4552986B2 (ja) 画像表示装置
US9286860B2 (en) Image display device
JP6237020B2 (ja) 画像表示装置、および画像表示装置の制御方法
JP2003162002A (ja) 投射型表示装置及び表示装置とその駆動方法
JP2006284982A (ja) 調光情報生成装置、その方法、そのプログラム、そのプログラムを記録した記録媒体、および画像表示装置
CN114584748A (zh) 激光投影设备、其显示方法及可读性存储介质
JP5326271B2 (ja) レーザ光源装置、映像表示装置
WO2022052867A1 (zh) 投影设备
JP4552985B2 (ja) 画像表示装置
JP2012113241A (ja) 画像表示装置、画像表示システム及び画像表示方法
JP2004309622A (ja) 画像表示装置とその階調表現方法、投射型表示装置
JP2004325644A (ja) プロジェクタ
JP2007094171A (ja) 映像表示制御装置、投写型映像表示装置及び背面投写型映像表示装置
JP4023125B2 (ja) 照明装置ならびに投射型表示装置とその駆動方法
JP5392345B2 (ja) プロジェクタ及びプロジェクタの制御方法
JP2009175771A (ja) プロジェクタの制御方法
JP7254466B2 (ja) 制御装置、投射型表示装置および記憶媒体
JP4461703B2 (ja) プロジェクタ
KR101008650B1 (ko) 투사형 표시 장치 및 화이트밸런스 조정 방법
JP2018010062A (ja) 投射型表示装置及び投射型表示装置の制御方法
JP2009085990A (ja) 映像表示装置及び制御装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21865921

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21865921

Country of ref document: EP

Kind code of ref document: A1