WO2018214153A1 - Automated compensation system and method for heat-caused defocusing - Google Patents

Abstract

An automated compensation system and method for heat-caused defocusing. During the use of a projection lens (10), if any of trigger conditions of heat-caused defocusing is met, compensation for the heat-caused defocusing is triggered. The method comprises steps of: acquiring, by means of moving a movable lens (101), at least two different real-time projection frames; analyzing sharpness of the at least two different real-time projection frames, and searching for a position of the movable lens (101) corresponding to the highest sharpness in a movable range; and controlling and positioning the movable lens (101) at the position of the highest sharpness in the movable range. The projection lens (10) can perform automated compensation and focus adjustment for heat-caused defocusing resulting from an internal temperature increase after startup. A projection frame has a small dedicated popup window to facilitate imaging sharpness analysis of the projection frame. The present invention enables automated and fast compensation and focus adjustment, thus reducing the influence of the compensation and focus adjustment on the smoothness of viewing experience.

Description

 System and method for automatic defocusing automatic compensation

Technical field

 [0001] The present invention relates to a thermal out-of-focus compensation method for a projection system, and more particularly to an automatic compensation method for thermal defocus of a projection system.

 Background technique

 [0002] The lenses of projection lenses are mostly glass or resin materials, and their characteristics are somewhat deformed with temperature changes. When the projector is down, there is always an internal temperature rise until it reaches the thermal balance. Therefore, before the thermal balance is reached after the machine is turned off, the imaging of the lens changes as the internal temperature rises, which requires a clear focus on the focus. The prior art has disclosed a thermal defocus compensation projector that sets a temperature sensor near the lens, detects the temperature value of the projection lens, and then emits a focus command through the focus motor, and the focus motor drives a group. After the lens is moved back and forth to perform the focusing operation, the image of the camera is adjusted to achieve a clear picture after thermal defocus compensation.

[0003] Although the screen of the projection device of the camera has undergone the first focusing, the projection lens is projected during the use due to the change of the ambient temperature and the internal temperature of the projector due to the change of the projection lens and the related construction. The lens always has the focal length of the projection lens (commonly known as hot running focus or thermal out of focus), so that the projected image of the projection lens will become blurred. Especially for small projectors with high heat dissipation challenges, it is a difficult problem in the industry. There is no ambiguity in the process of use, except that there is no better way to re-focus manually after the thermal out of focus.

 technical problem

 [0004] The technical problem of the present invention is that, in view of the above-mentioned deficiencies of the prior art, the present invention provides a system and method for automatic thermal defocusing compensation, which is caused by temperature changes during use of a projection lens. Trigger automatic compensation focusing;

[0005] Another projection window of the system and method for automatically defocusing automatic compensation has a special small pop-up window for displaying fixed content, and is convenient for analyzing the image clarity of the projected image in any projection screen background; [0006] The present invention provides another system and method for automatic thermal defocusing compensation, in the use of a projection lens, automatic tuning The focal movement range is smaller than the first focusing movement range of the cymbal cymbal, and since it is automatically compensated for focusing, the effect of compensating focusing on viewing fluency is reduced.

 Problem solution

 Technical solution

 [0007] In order to achieve the above object, the present invention provides a method for automatically offsetting thermal out-of-focus, which is characterized in that, in the process of using the projector, the projection system satisfies any trigger condition of the thermal defocus compensation, and triggers the thermal defocus compensation. The method includes the steps of: acquiring at least two frames of different real projection images by moving the movable lens; analyzing the sharpness of the at least two different suitable projection images, and finding the movable lens corresponding to the highest resolution in the moving range; Position; and control the position where the movable lens falls within the highest range of clarity in the range of movement

[0008] wherein, the preferred solution is: the trigger condition is to reach the preset time after the downtime or the first focus adjustment.

 [0009] wherein, the preferred solution is: the trigger condition is that the temperature near the projection lens reaches or exceeds one or more specific thresholds.

 [0010] wherein, the preferred solution is: the trigger condition is that the resolution of the monitoring lens does not meet the definition requirement.

 [0011] wherein, the preferred solution is: the projection system is 幵, the moving range L1 of the movable lens is smaller than the moving range L0 in the first focusing process.

[0012] wherein, the preferred solution is: the projection screen includes a dedicated pop-up window to display fixed content, and is used for image sharpness analysis of the projection screen.

 [0013] The present invention also includes a system for automatic thermal defocusing compensation, comprising at least one set of projection lenses that can be moved back and forth within a focus range, and a focus motor that drives the movement of the projection lens, characterized in that The method further includes: a signal processing module, a projection lens, a monitoring lens, a focus motor, and a signal processing module electrically connected, and the projection system meets any trigger condition of the thermal out-of-focus compensation during the use of the machine, triggering the thermal defocus Compensating the lens, acquiring at least two frames of different real projection images; the signal processing module analyzing the sharpness of the real projected image, finding the movable lens position corresponding to the highest sharpness value in the moving range; controlling the movable lens falling The position with the highest sharpness in the range of movement.

 [0014] wherein, the preferred solution is: the moving range L1 of the movable lens is smaller than the moving range L0 in the first focusing process.

[0015] wherein, the preferred solution is: the projection screen is provided with a dedicated pop-up window, and the fixed content is displayed for the cast Image sharpness analysis of the shadow picture.

 [0016] Wherein, a preferred solution is: installing a temperature sensor near the projection lens to monitor an internal temperature of the projection lens.

 Advantageous effects of the invention

 Beneficial effect

 [0017] The beneficial effects of the present invention are: during the use of the projection lens, the running focus and the triggering automatically compensate for the focusing due to the temperature change; the system and the method automatically compensate the focusing image during the focusing process. Pop-up window, display fixed content, in the background of any projection screen, it is convenient to analyze the image clarity of the projected image; in addition, in the use of the projection lens, the auto-focusing movement range is smaller than the first focusing movement range of the 吋 吋, Because it is automatically compensated for focusing and the focusing process is short, the effect of compensation focusing on viewing fluency is reduced.

 Brief description of the drawing

 DRAWINGS

 [0018] The present invention will be further described below in conjunction with the accompanying drawings and embodiments, in which:

1 is a schematic structural view of a first embodiment of a system for automatically defocusing automatic compensation according to the present invention;

2 is a schematic structural view of a second embodiment of a system for automatically defocusing automatic compensation according to the present invention;

3 is a comparison view of displacement of the first focusing of the present invention and the automatic defocusing automatic focusing of the present invention;

4 is a flow chart of a first embodiment of a method for automatic thermal defocusing compensation according to the present invention;

5 is a flow chart of a first embodiment of a method for automatic thermal defocusing compensation according to the present invention.

 BEST MODE FOR CARRYING OUT THE INVENTION

 BEST MODE FOR CARRYING OUT THE INVENTION

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0024] A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[0025] As shown in FIG. 1, in the first embodiment of the present invention, the projection lens 10 and the focus motor 30 are further included, and a monitoring lens 20 and a signal processing module 40 are included. The projection lens 10 includes at least one set of movable lenses 101 that can be moved back and forth within a focus range, the movable lens 101 and the focus motor 30 are drivingly connected, and the focus motor 30 drives the movable lens 101 to be adjusted. Moving forward and backward within the focal range; the monitoring lens 20 monitors the projection image of the projection lens 50 for image sharpness information transmission The signal processing module 40 receives and analyzes the projection image resolution information; the focus motor 30 drives the resolution information according to the projection image 50 processed by the signal processing module 40 to drive the movable lens 101 mobile. In the actual focusing process, at least two different frame projection images are acquired by moving the movable lens 101; analyzing the resolution of the at least two frames of different real projection images, and finding the highest resolution value in the moving range. Movable lens position; controls the position where the movable lens falls within the highest definition of the range of motion.

 The projection lens 10, the monitoring lens 20, and the focus motor 30 are electrically connected to each other and the signal processing module 40. When the automatic compensation focus adjustment condition is satisfied, the projection lens 10 is in a non-central area of the projection screen 50. A special pop-up window 501 is displayed, and the special pop-up window displays the fixed content. The pop-up window content can be text or image or text + image, and the monitoring lens 20 captures at least two frames of different dedicated pop-up pictures to the signal processing module 40. Performing the comparison analysis, analyzing the sharpness of the image of the special pop-up window, finding the position of the movable lens corresponding to the highest value of the sharpness in the moving range, instructing the focus motor 30 to move the movable lens 101 back and forth, and controlling the movable lens to fall on The position with the highest resolution in the range of motion is completed, and the automatic compensation focusing operation is completed. The advantage of the special pop-up window is that when the projection picture is a solid color picture or a dark field picture, it is difficult to analyze the image of the projection picture captured by the monitoring lens 20, and the special pop-up picture is used instead of the projection picture for comparison analysis. , you can easily find the picture with the highest resolution and the corresponding position, which means that the thermal out of focus can automatically compensate the focus in any projection background.

[0027] wherein the focus motor 30 includes a voice coil motor, a stepping motor or a servo motor.

2 is a second embodiment of the system for automatically losing thermal out of focus according to the present invention. In this embodiment, a temperature sensor 60 is added for monitoring the temperature in the vicinity of the projection lens 10. When the internal temperature of the temperature sensor test reaches or exceeds one or more specific thresholds, the projection system displays a dedicated pop-up window 501 in the non-central area of the projection screen 50 through the projection lens 10, and the dedicated pop-up window displays the fixed content, the pop-up window content. Can be text or image or text + image, the surveillance lens 20 will capture at least two frames of different dedicated pop-up pictures to the signal processing module 40 for comparison analysis, analyze the clarity of the special pop-up picture, find The position of the movable lens corresponding to the highest resolution value in the range of movement, the command focus motor 30 drives the movable lens 101 to move back and forth, and controls the movable lens to fall within the position of the highest definition value in the moving range, and completes the automatic compensation focusing operation.

3 is a comparison view of displacement of the first focus adjustment and the thermal defocusing auto focus of the present invention, as shown in FIG. 3, the first focus adjustment In order to adjust the focus of the machine, the focusing process starts from zero point 01. After the best clear point T1, it returns from the T2 point to stop at the T1 point, and the focusing range is L0; the thermal out of focus automatically compensates for the focus, Moving from point T1 to point B1, the signal processing module finds that the pop-up information is getting more and more blurred, and will instruct the focus motor to move in the opposite direction. After the best clear point A, it will return from point B2 to stop at point A. The focusing range is Ll. Since the back focus position of the thermal defocusing projection lens is very close to the back focus position after the first focusing, the range of the thermal out of focus automatic compensation focusing is smaller than the range L0 of the first focusing. Many, because the automatic compensation focusing process is short, the effect of compensation focusing on viewing fluency is reduced.

 4 is a flow chart of a method for automatic thermal defocusing compensation according to the present invention, as shown in FIG. 3: The projection lens 10 starts to work, first performs focusing, and when the resolution of the projection screen 50 is Below the preset threshold, or the resolution of the previous focus is lower than a fixed value or the percentage of the last focus

(For example, 80%) 吋 In this embodiment, the predetermined start time is a preset length of the start time, such as a preset time of 10 minutes, projection. During the use of the system, when the fixed decoupling compensation is satisfied, at least two different frame projection images are acquired by moving the movable 101; the signal processing module 40 analyzes the resolution of the actual projection images of the at least two frames. Finding the position of the movable lens 101 corresponding to the highest value of the sharpness in the moving range; the signal processing module 40 controls the focus motor 30 to move the lens 101 to the position where the sharpest value of the moving lens falls within the moving range, then the first time in the downtime or the first time After focusing, an automatic compensation focus is performed every 10 minutes.

 5 is a flow chart of another embodiment of a method for automatic thermal defocusing compensation according to the present invention. Compared with the previous embodiment, the present embodiment adds a temperature sensor 60 to the projection system for monitoring the Projection system internal temperature. In this embodiment, the temperature in the vicinity of the projection lens 10 is monitored. In this embodiment, the trigger condition for one or more automatic compensation of the focus adjustment is when the internal temperature of the temperature sensor test reaches or exceeds one or more specific thresholds. In the embodiment, four temperature thresholds are set, which are 10 ° C, 20 ° C, 30 ° C, and 40 ° C, respectively. If the temperature monitored by the first focus temperature sensor is 25 ° C, then the temperature sensor When the monitored temperature reaches 30 °C, it will trigger the automatic compensation focus adjustment. When the temperature continues to rise and the temperature sensor monitors the temperature to 40 °C, the automatic compensation focus will be triggered again, and vice versa.

[0032] The invention causes the running focus and the 吋 trigger compensation focusing during the use of the projection lens during the use of the projection lens; the system and the method automatically compensate the focusing process with a special small pop-up window to display the fixed content, In the background of any projection screen, it is convenient to analyze the image clarity of the projected image; In use, the automatic compensation focusing movement range is smaller than the first focusing movement range of the 吋 ,, because it is automatically compensated for focusing and the focusing process is short, which reduces the influence of compensation focusing on viewing fluency.

 It should be understood that the above embodiments are only used to illustrate the technical solutions of the invention, and are not limited thereto. For those skilled in the art, the technical solutions described in the foregoing embodiments may be modified, or some of the technical features may be performed. All such modifications and substitutions are intended to fall within the scope of the appended claims.

Claims

A method for automatically offsetting thermal out-of-focus is characterized in that: when the projection system meets any trigger condition of thermal defocus compensation during the use of the downtime, the thermal defocus compensation is triggered, including the steps: moving by moving a lens, acquiring at least two frames of different real projection images; analyzing the resolution of the at least two frames of different real projection images, and finding a movable lens position corresponding to the highest resolution value in the moving range;  Controls the position at which the movable lens falls within the highest definition of the range of motion.  The method of automatic thermal defocusing compensation according to claim 1, wherein the triggering condition is a preset time after reaching the downtime or the first focusing.  The method of automatic thermal defocusing compensation according to claim 1, wherein the triggering condition is that a temperature in the vicinity of the projection lens reaches or exceeds one or more specific thresholds.  A method of automatic thermal defocusing compensation according to claim 1, wherein: the triggering condition is that the sharpness of the monitoring lens does not satisfy the sharpness requirement.  The method of automatic thermal defocusing compensation according to claim 1, wherein: the moving range L1 of the movable lens is smaller than the moving range of the movable lens during the first focusing process. [Claim 6] The method of automatic thermal defocusing compensation according to claim 1, wherein: the projection screen has a dedicated pop-up window for displaying fixed content for image sharpness analysis of the projection screen.  [Claim 7] A system for automatic thermal defocusing compensation, comprising a projection system and comprising at least one set of movable lenses movable back and forth within a focus range, and a focus motor driving the movable lens to move, The method further includes: a signal processing module, and a projection lens electrically connected to the signal processing module, a monitoring lens, a focus motor, and the projection system meets any trigger condition of the thermal defocus compensation during the use of the machine, triggering Thermal out of focus compensation;  The monitoring lens acquires at least two frames of different real projection images;  The signal processing module analyzes the sharpness of the projected image and finds the clarity within the moving range; The highest value corresponds to the position of the movable lens; controlling the movable lens to fall within the range of movement The location with the highest value.  [Claim 8] The system of automatic defocusing automatic compensation according to claim 7, wherein: the moving range L1 of the movable lens is smaller than the moving range L0 in the first focusing process.  [Claim 9] The thermal defocusing automatic compensation system according to claim 7, wherein: the projection screen is provided with a dedicated pop-up window for displaying fixed content for image sharpness analysis of the projection screen.  [Claim 10] The thermal defocusing automatic compensation system according to claim 7, wherein a temperature sensor is installed in the vicinity of the projection lens to monitor an internal temperature of the projection lens.