A method for automatically adjusting focus area in a projector

Abstract

The present invention provides a method for automatically adjusting a focus area in a projector, comprising: placing the projector at a focus position 2 meters away from a projection screen, first performing focus, printing a focus picture, adjusting the focus picture to be clear, and recording the positions of the four sides of the focus picture with black tape; detecting a viewfinder position, calling out a viewfinder screen of a camera, and observing whether four viewpoints in the viewfinder screen are within the viewfinder; adjusting the viewfinder position based on the positions of the four sides of the focus picture recorded with the black tape, keeping the viewfinder position under the viewfinder screen of the camera, and adjusting the position of the viewfinder according to a current x offset, a y offset, and a saved offset; when the four viewpoints in the viewfinder screen are adjusted to be within the viewfinder, pressing a confirm key, fixing the coordinate parameters of the viewfinder and saving them in a system flash; the method provided by the present invention dynamically adjusts the focus area during production, and ultimately ensures that the focus picture falls within the focus area, thereby effectively improving user experience.

Description

Technical Field

[0001] The present invention relates to the field of projector focus adjustment, and in particular to a method for automatically adjusting a focus area in a projector. Background Art

[0002] The demand for projector autofocus arises from the following scenarios: In the past, most projectors were ceiling-mounted and did not require users to manually adjust the focus. However, with the development of LED projection, most home projectors or micro projectors no longer require ceiling mounting. Users often need to move the projection position during daily use, and they need to manually readjust the focus each time they move to a new location. This does not provide a very good user experience. In order to free users from manual focus, micro projectors have introduced an autofocus function.

[0003] In the micro projector industry, autofocus is generally achieved using a camera. There are two options for focusing:

[0004] 1) Global focus: This method focuses the entire area the camera can see. This method has an obvious disadvantage because, in general, the area the camera sees is not just the projection area, but also the external area. At this time, the camera is easily affected by the external image and light, which can cause focus failure and affect the clarity of the projector's projection image.

[0005] 2) Local focus: Local focus does not focus on the entire area, but only on a local area (usually a small area in the middle of the projection area). It requires a focus pattern. When autofocusing, a focus pattern will be printed out and the camera will obtain the clarity of the focus pattern to achieve autofocus. This solution can achieve an ultra-small focus pattern, and the focus pattern will hardly affect the projected image during focusing, which can effectively improve the user experience. However, this focus solution also has a fatal flaw. Due to errors in assembly, structure, and patching, the focus pattern may sometimes not be within the focus area and may move outside the focus area. In addition, due to the influence of errors in assembly, structure, and patching, the relative error between the focus pattern and the focus area is inconsistent and very divergent, making it impossible to effectively control the error by improving the structure. Existing technologies typically address this issue by expanding the focus area. Some solutions extend the focus area to the entire visible range of the camera. However, expanding the focus area also adds unnecessary surrounding reference objects to the focus area, and also increases the impact of ambient light on the focus area, resulting in a significant decrease in focus accuracy and success rate. Furthermore, because the errors are inconsistent and widely divergent, there is no way to improve them through data compensation. Summary of the Invention

[0006] The main purpose of the present invention is to overcome the above-mentioned defects in the prior art and propose a method for automatically adjusting the focus area in a projector. This method can dynamically adjust the focus area during production, and ultimately allow the focus pattern to fall within the focus area, which can effectively improve the user experience.

[0007] The present invention adopts the following technical solutions:

[0008] A method for automatically adjusting a focus area in a projector, comprising:

[0009] Place the projector at the focus position of the projection screen, perform focus first, print out the focus picture, adjust the focus picture to be clear, and use black tape to record the position around the focus picture;

[0010] Detect the position of the viewfinder, call up the camera's viewfinder image, and observe whether the four viewing points in the viewfinder image are within the viewfinder;

[0011] Adjust the viewfinder position based on the positions of the four sides of the focused image recorded with the black tape. Keep the camera's viewfinder in view and adjust the viewfinder position based on the current x-offset, y-offset, and the saved offset.

[0012] When the four viewing angles in the viewfinder screen are adjusted to be within the viewfinder frame, press the OK key to fix the coordinate parameters of the viewfinder frame and save them in the system flash.

[0013] Specifically, it also includes:

[0014] When focusing again, the coordinate parameters of the viewfinder saved in the flash are read out, and the coordinate parameters of the viewfinder are used as new coordinates for focusing.

[0015] Specifically, it also includes: adjusting the viewfinder position based on the positions of the four sides of the focused image recorded by the black tape, specifically:

[0016] The viewfinder position falls completely within the area around the focused image recorded by the black tape.

[0017] Specifically, the method further includes: adjusting the position of the viewfinder according to the current x offset, y offset, and the saved offset; and further including:

[0018] If focusing at close range, make the focused image on the right side of the focus frame;

[0019] If you are focusing at a long distance, make the focused image on the left side of the focus frame.

[0020] From the above description of the present invention, it can be seen that compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention provides a method for automatically adjusting the focus area in a projector, comprising: placing the projector at a focus position 2 meters away from a projection screen, first performing focus, printing a focus image, adjusting the focus image to be clear, and recording the positions of the four surrounding areas of the focus image with black tape; detecting the position of the viewfinder, calling up the camera's viewfinder screen, and observing whether the four viewing points in the viewfinder screen are within the viewfinder; adjusting the viewfinder position based on the positions of the four surrounding areas of the focus image recorded with the black tape, keeping the viewfinder within the camera's viewfinder screen, and adjusting the position of the viewfinder based on the current x-offset, y-offset, and saved offsets; and when the four viewing points in the viewfinder screen are adjusted to be within the viewfinder, pressing a confirm key to fix the coordinate parameters of the viewfinder and save them in a system flash memory. The method of the present invention can dynamically adjust the focus area during production, ultimately ensuring that the focus pattern falls within the focus area, thereby effectively improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A flow chart of a method for automatically adjusting a focus area in a projector provided by an embodiment of the present invention;

[0023] Figure 2 An example diagram of the positions of the four sides of a focused image recorded with black tape provided in an embodiment of the present invention;

[0024] Figure 3 An example diagram of a camera viewfinder provided in an embodiment of the present invention;

[0025] Figure 4 An example diagram of the process of adjusting the viewfinder position provided by an embodiment of the present invention;

[0026] Figure 5 Another exemplary diagram of the process of adjusting the viewfinder position provided by an embodiment of the present invention;

[0027] Figure 6 This is an example diagram of the adjusted viewfinder position provided by an embodiment of the present invention.

[0028] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. DETAILED DESCRIPTION

[0029] The present invention realizes the focus debugging mode function. In this mode, the camera will play back the recorded image information in real time through an optical machine, and at the same time of playback, the focus area will be projected, so that the operator can see the focus area in real time, and the real-time adjustment function of the viewfinder can be realized. This function can receive the user's key information, and dynamically adjust the up, down, left and right positions of the focus area according to the up, down, left and right keys to realize the function of saving and reading the focus area coordinate information. Under the focus debugging mode function, after the user adjusts the focus area, he clicks the OK key to save the coordinate parameters of the focus area in the flash. The next time focusing, the coordinate information saved in the flash is read out, and the focus is performed with the new coordinates.

[0030] like Figure 1 , is a flow chart of the method of the present invention, which specifically includes:

[0031] S1: Place the projector at the focus position 2 meters away from the projection screen. First, perform focus and print out the focus picture. Adjust the focus picture so that it is clear and easy to locate. Use black tape to record the position of the focus picture around it, as shown below. Figure 2 As shown, black tape is used to stick around the focused image to locate the position of the focused image.

[0032] S2: Detect the position of the viewfinder;

[0033] a. Press the Back button twice to exit the focused interface and return to the main interface.

[0034] b. Press the Source button on the remote control to switch to HDMI source.

[0035] c. Press the left button -> right button -> left button -> right button -> left button -> right button on the remote control in sequence to bring up the camera's viewfinder, as shown below Figure 3 As shown;

[0036] S3: Check whether the four points marked by the red box in the above picture are within the viewfinder

[0037] These four black dots are the camera's framing, and then they are displayed through the projector, so you will see an overlapping effect. We only need to look at the display on the outside, and we can also view it by connecting a monitor. If you view it directly through an external monitor, there will be no overlapping. In this interface, we mainly need to confirm whether the four points marked with a red frame are in the framing frame. If not, it means that when focusing, when the focus picture is printed, the focus picture will not completely fall within the focus area, so the success rate of focusing will be relatively low. Therefore, this focus area is crucial. If the focus picture is not in the framing frame, you need to manually adjust the position of the framing frame. As shown in the figure above, there is a marked point that is not in the bright frame of the framing. At this time, you need to adjust it to fall within the bright frame of the framing to achieve the best focus effect.

[0038] S4: Adjust the viewfinder position

[0039] a. Keep the camera in the viewfinder and press the menu button. The operation prompt menu will be displayed on the right. Follow the prompts in the menu to perform the operation. Figure 4 As shown;

[0040] b. Press the menu key to start adjustment, use the up, down, left, and right keys to shift in single steps, and press the ok key to save.

[0041] c. The current x,y offset and the saved offset are displayed below.

[0042] d. The green box at the bottom is x,y=0,0, and the red box is the relative position of the offset;

[0043] e. At this time, you can press the up, down, left, and right keys to adjust the position of the viewfinder. The adjustment process is as follows: Figure 5 As shown;

[0044] Because the camera and optical machine are placed in parallel, they have the following characteristics:

[0045] If you focus very close, such as 0.7 meters, the focus pattern will be on the right side of the focus frame;

[0046] If you are focusing far away, such as 2 or 3 meters, then the focus pattern will be on the left side of the focus frame.

[0047] So when adjusting the focus position, if the distance is 2 meters, try to adjust the focus pattern to the left, as shown below Figure 6 The adjusted viewfinder position was made at 2.5 meters and moved to the far left (the four o'clock position is on the left side of the viewfinder).

[0048] The adjustment process is displayed in real time, allowing you to see the effect of the adjustment. When all four black dots in the focused image are within the viewfinder, press the OK button. The saved value will be displayed in green text, and the viewfinder position will be fixed and saved to the system flash. This completes the focus area adjustment. The next time you focus, the new parameters will be used.

[0049] The above is only a specific implementation of the present invention, but the design concept of the present invention is not limited to this. Any non-substantial changes to the present invention using this concept shall be deemed as an infringement of the protection scope of the present invention.

Claims

1. A method for automatically adjusting a focus area in a projector, characterized in that: include: Place the projector at the focus position 2 meters away from the projection screen. Focus first, print the focus image, adjust the focus image until it is clear, and use black tape to record the position around the focus image. Detect the position of the viewfinder, call up the camera's viewfinder image, and observe whether the four viewing points in the viewfinder image are within the viewfinder; Adjust the viewfinder position based on the positions of the four sides of the focused image recorded with the black tape. Keep the camera's viewfinder in view and adjust the viewfinder position based on the current x-offset, y-offset, and the saved offset. When the four viewing angles in the viewfinder screen are adjusted to be within the viewfinder frame, press the OK key to fix the coordinate parameters of the viewfinder frame and save them in the system flash.

2. The method for automatically adjusting the focus area in a projector according to claim 1, wherein: Also includes: When focusing again, the coordinate parameters of the viewfinder saved in the flash are read out, and the coordinate parameters of the viewfinder are used as new coordinates for focusing.

3. The method for automatically adjusting the focus area in a projector according to claim 1, wherein: Also includes: Adjust the viewfinder position based on the positions of the four sides of the focused image recorded by the black tape, specifically: The viewfinder position falls completely within the area around the focused image recorded by the black tape.

4. The method for automatically adjusting the focus area in a projector according to claim 1, wherein: Also includes: Adjust the position of the viewfinder based on the current x offset, y offset, and the saved offsets. This also includes: If focusing at close range, make the focused image on the right side of the focus frame; If you are focusing at a long distance, make the focused image on the left side of the focus frame.

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