Desktop remote image read-write device with contrast control and control method thereof

Abstract

The invention discloses a desktop remote image read-write device with contrast control and a control method thereof. The desktop remote image read-write device comprises a plane spectroscope, a concave reflector and a backlight plate. The light reflected by the desktop and an object placed on the desktop is emitted to the plane spectroscope from the lower part, and the light split by the plane spectroscope is reflected by the concave reflector, is split by the plane spectroscope again, is emitted to an exit pupil position and forms a far image at a position not less than 3 meters; brightness of different areas of the backlight plate is different so as to change contrast of different areas of a far image. According to the desktop far image read-write device, when a user reads characters and other contents in a book, the peripheral low-contrast visual effect is provided, the growth of an eye axis is further inhibited, meanwhile, a certain effect is achieved on thickening of a choroid, and myopia prevention and control are achieved.

Description

Technical Field

[0001] The invention relates to a desktop telescopic reading and writing device with contrast control, and also relates to a control method of the desktop telescopic reading and writing device, belonging to the field of myopia prevention and control equipment. Background Art

[0002] Myopia is a growing problem among teenagers. The root cause is that teenagers spend most of their time focusing on close-up objects. To adapt to close-up imaging, their eye axes gradually lengthen. To address this issue, various myopia prevention and control products have emerged on the market.

[0003] Desktop telephoto reading and writing devices, which use optical means to extend short-range reading and writing to distant imaging, are often used in the prevention and control of myopia in adolescents. However, the effectiveness of long-range imaging using a single optical path is limited for myopia prevention and control, and therefore, other auxiliary methods are needed to enhance myopia prevention and control. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a desktop telephoto reading and writing device with contrast control.

[0005] Another technical problem to be solved by the present invention is to provide a control method for a desktop telescopic reading and writing device.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0007] According to one aspect of the present invention, a desktop telephoto reading and writing device with contrast control is provided, comprising: a plane beam splitter, a concave reflector and a backlight panel; wherein,

[0008] The concave reflector is kept in a horizontal or vertical position when in use; the plane beam splitter is tilted when in use;

[0009] The backlight plate and the concave reflector are arranged perpendicular to each other and are used to provide light to the exit pupil position;

[0010] The light reflected by the table and the objects placed on the table is emitted from below to the plane beam splitter. The light formed after the light is split by the concave reflector is reflected by the concave reflector and then split by the plane beam splitter. The light is emitted to the exit pupil position and forms a distant image at a position of not less than 3 meters. The brightness of different areas of the backlight panel is different, thereby changing the contrast of different areas of the distant image.

[0011] Preferably, the desktop telescopic reading and writing device further comprises an eye tracking camera and a controller;

[0012] The eye tracking camera is arranged facing the exit pupil position and is used to capture images of the human eye;

[0013] The controller determines the gaze point of the human eye in the distant image according to the human eye image, and makes the brightness of the gaze area centered on the gaze point in the backlight panel lower than the brightness of the area around the gaze area.

[0014] Preferably, in the backlight panel, the array light source covers the entire area of ​​the backlight panel, and the controller makes the light source in the viewing area have low brightness or does not emit light.

[0015] Preferably, the backlight panel includes a fixed white board and a dark electrochromic film covering it, and the transmittance of the electrochromic film at different positions at different times is controlled by a logic timing circuit to change the brightness of different areas of the backlight panel.

[0016] Preferably, in the backlight panel, the array light sources are distributed only in a peripheral area of ​​the backlight panel, or only in one or more local areas.

[0017] Preferably, the backlight panel is replaceable, and different backlight panels have different arrangements of the array light sources.

[0018] Preferably, the desktop telescopic reading and writing device further comprises:

[0019] The first adjusting member is used to adjust the angle between the plane beam splitter and the concave reflecting mirror, and maintain the plane beam splitter at at least two positions where the angle between the plane beam splitter and the concave reflecting mirror is between 30° and 60°; the angle between the plane beam splitter and the concave reflecting mirror is adjusted by the first adjusting member to change the height of the exit pupil position relative to the desktop.

[0020] Preferably, the desktop telescopic reading and writing device further comprises:

[0021] The fill light is arranged on the lower surface of the plane beam splitter. The fill light is composed of multiple light sources arranged linearly. The multiple light sources are arranged in a stepped manner. Moreover, when the plane beam splitter and the desktop are at a 45° angle, the main light of each light source is perpendicular to the desktop.

[0022] According to another aspect of the present invention, a control method for a desktop telephoto reading and writing device is provided, characterized by comprising the following steps:

[0023] The desktop telescopic reading and writing device comprises: a plane beam splitter, a concave reflector and a backlight panel; wherein,

[0024] The light reflected by the table and the objects placed on the table is emitted from below to the plane beam splitter. The light formed after the light is split by the concave reflector is reflected by the concave reflector and then split by the plane beam splitter. The light is emitted to the exit pupil position and forms a distant image at a position of not less than 3 meters. The backlight panel is arranged facing the exit pupil position and has different brightness in different areas, thereby changing the contrast of different areas of the distant image.

[0025] Preferably, eye tracking camera is used to capture the image of the human eye; the controller determines the gaze point of the human eye in the distant image based on the image of the human eye, and makes the brightness of the light source in the gaze area centered on the gaze point in the backlight panel lower than the brightness of the light source in the area surrounding the gaze area.

[0026] Preferably, the range of the gaze area is not larger than the size of the area in the backlight panel 12 corresponding to the ±12° visual field of the human eye, and is not smaller than the size of the area in the backlight panel 12 corresponding to the ±3° visual field of the human eye.

[0027] Preferably, the range of the gaze area is a circular area centered on the gaze point, and the diameter of the circular area is 6 to 8 centimeters.

[0028] Preferably, the brightness of the light source in the area outside the gaze area increases in steps with the gaze point as the center.

[0029] Preferably, the entire backlight panel presents a brightness that gradually increases from the center to the outside with the gaze point as the center.

[0030] The desktop telephoto reading and writing device with contrast control provided by the present invention uses a coaxial optical system to image the reflected light from the desktop and objects placed on it. Simultaneously, by adding a backlight panel and varying the brightness of different areas of the backlight panel, the contrast of different areas of the telephoto image is varied, achieving the purpose of myopia prevention and control. This desktop telephoto reading and writing device with contrast control incorporates contrast control while forming the telephoto image. When the user is reading text or other content in a book, it simultaneously provides a low-contrast visual effect in the peripheral area, further inhibiting the growth of the eye axis and having a certain effect on choroidal thickening, achieving myopia prevention and control. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 1 is a schematic structural diagram of a desktop telephoto reading and writing device with contrast control provided in Example 1 of the present invention;

[0032] Figure 2 yes Figure 1 The diagram below shows the principle of optical path of horizontal exit pupil of desktop telephoto reading and writing device;

[0033] Figure 3A and Figure 3B yes Figure 1The diagram shows two optical path principles of a desktop telephoto reading and writing device with tilted exit pupil;

[0034] Figure 4 is a schematic diagram of the adjustment structure of the desktop telephoto reading and writing device shown in Example 1;

[0035] Figure 5 yes Figure 1 Schematic diagram of the arrangement of the array light source;

[0036] Figure 6 This is a schematic structural diagram of a desktop telescopic reading and writing device with low contrast in the peripheral area provided by Example 2 of the present invention. DETAILED DESCRIPTION

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0038] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0039] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0040] The present invention aims to provide a desktop telephoto reading and writing device with contrast control based on a coaxial optical system. Figure 1As shown, the desktop telephoto reading and writing device with contrast control provided by the present invention includes: a support plate 3, a plane beam splitter 1, a concave reflector 2, and a backlight plate 12; wherein one end of the concave reflector 2 is connected to one end of the support plate 3 and is maintained at a position perpendicular to the support plate 3 when in use; the plane beam splitter 1 is tilted and arranged between the concave reflector 2 and the support plate 3 when in use; the backlight plate 12 is arranged on the side of the support plate 3 facing the exit pupil, and is used to provide light to the exit pupil position; light reflected by the table 4 and objects placed on the table is emitted from below to the plane beam splitter 1, and the light split by the plane beam splitter 1 is emitted to the concave reflector 2, and then, after being reflected by the concave reflector 2, is split by the plane beam splitter 1 and emitted to the exit pupil position, and forms a telephoto image at a position not less than 3 meters. The backlight plate 12 is arranged on the side of the support plate 3 facing the exit pupil, and the backlight plate 12 includes an array light source, which is used to provide light to the exit pupil position; the brightness of different areas of the backlight plate 12 is different, thereby changing the contrast of different areas of the telephoto image, thereby achieving contrast control.

[0041] The positions of the support plate 3 and the concave reflector 2 can be interchanged. Figure 1 As shown, the support plate 3 can be vertically arranged at the top of the bracket 9, and in this case, the concave reflector 2 is horizontally arranged when in use. It is understandable that the support plate 3 can also be horizontally arranged when in use, while the concave reflector 2 is vertically arranged at the top of the bracket. Because whether the setting positions of the support plate 3 and the concave reflector 2 are interchangeable has no effect on the imaging principle of the fixed desktop telescopic reading and writing device, the setting positions of the support plate 3 and the concave reflector 2 are not limited here. The following is an example of a desktop telescopic reading and writing device in which the support plate 3 is vertically arranged at the top of the bracket 9 and the concave reflector 2 is horizontally arranged when in use.

[0042] like Figure 1 The desktop telescopic reading and writing device with contrast control shown in the figure comprises: a plane beam splitter 1, a concave reflector 2, a support plate 3 and a bracket 9; wherein, the bracket 9 is vertically arranged on the desktop 4, the support plate 3 is vertically arranged and connected to the top of the bracket 9; one end of the concave reflector 2 is connected to the top of the support plate 3 and is maintained in a position parallel to the desktop 4 when in use; the top of the plane beam splitter 1 can rotate around the top of the support plate 3, and the plane beam splitter 1 is tilted and arranged between the concave reflector 2 and the support plate 3 when in use, and the light reflected by the desktop 4 and the objects placed on the desktop is emitted from below to the plane beam splitter 1, passes through the plane beam splitter 1 and then emits to the concave reflector 2 and is reflected at the position of the concave reflector 2; the light formed after reflection by the concave reflector 2 is reflected by the plane beam splitter 1 and emitted to the exit pupil position; the light emitted to the exit pupil position forms a telescopic image at a virtual image position not less than 3 meters in front of the exit pupil position.

[0043] In the desktop telephoto reading and writing device, the surface of the concave reflector 2 used for imaging is covered with a total reflection film; the curvature radius of the concave reflector 2 ranges from 800mm to 1300mm. The pupil distance of the desktop telephoto reading and writing device is between 150mm and 350mm, and the pupil diameter is not less than The field of view angle is not less than 35° and not more than 50°.

[0044] Table 1 gives the surface parameters of a group of optical elements in the telephoto optical path of the desktop telephoto reading and writing device.

[0045] Table 1 Surface parameters of each optical element in the telephoto optical path

[0046]

[0047]

[0048] As shown in Table 1, the specific optical design of the desktop telephoto reading and writing device with contrast control has an exit pupil distance of 200 mm and an exit pupil diameter of The horizontal field of view angle is ±19°, and the vertical field of view angle is ±14°.

[0049] In order to adapt to people of different heights, the plane beam splitter 1 can also be rotated. By rotating the plane beam splitter 1, the direction of the light reflected by the plane beam splitter 1 and directed to the exit pupil position can be changed, and the normal direction and height of the exit pupil position can be changed, which can avoid changing the virtual image position due to adjusting the height of the device. Figure 2 、 Figure 3A and 3B As shown, by changing the angle γ between the plane beam splitter 1 and the concave reflecting mirror 2 (γ is between 30° and 60°), the height of the exit pupil position relative to the desktop can be adjusted.

[0050] Among them, Figure 2 As shown, the plane beam splitter 1 is located at a 45° angle to the horizontal line (desktop). At this time, the light formed after being reflected by the concave reflector 2 is reflected by the plane beam splitter 1 and emitted toward the exit pupil position 5 in a horizontal direction. At this time, the normal direction of the exit pupil position 5 is parallel to the desktop 4. This position corresponds to the horizontal exit pupil position and can be used as the initial exit pupil position. At this time, the exit pupil plane is a vertical plane.

[0051] like Figure 3AAs shown, by lifting the plane beam splitter 1 upward, the angle between the plane beam splitter 1 and the horizontal line is less than 45°. At this time, the light formed after being reflected by the concave reflector 2 is reflected by the plane beam splitter 1 and emitted toward the exit pupil position 6 in an oblique upward direction. At this time, the normal direction of the exit pupil position 6 forms an acute angle with the desktop. The person's line of sight is slightly downward, the exit pupil position 6A is higher than the exit pupil position 5, the exit pupil position has changed in height relative to the desktop, and the exit pupil plane has tilted relative to the horizontal plane and the vertical plane.

[0052] like Figure 3B As shown, by pressing down the plane beam splitter 1, the angle between the plane beam splitter 1 and the horizontal line is greater than 45°. At this time, the light formed after being reflected by the concave reflector 2 is reflected by the plane beam splitter 1 and emitted toward the exit pupil position 6B in an inclined downward direction. At this time, the normal direction of the exit pupil position 6 forms an acute angle with the desktop. The person's line of sight is slightly downward, the exit pupil position 6B is lower than the exit pupil position 5, the exit pupil position has changed in height relative to the desktop, and the exit pupil plane has tilted relative to the horizontal plane and the vertical plane.

[0053] It can be understood that in this adjustable desktop telescopic reading and writing device, the positions of the support plate and the concave reflector can be interchanged, wherein the concave reflector is set vertically, the support plate is set horizontally, and the support plate remains in a position parallel to the desktop when in use; one end of the support plate is connected to the top of the concave reflector, and the top of the plane beam splitter is connected to the support plate or the concave reflector and can rotate around the top of the concave reflector, and the plane beam splitter is tilted between the concave reflector and the support plate when in use.

[0054] like Figure 4 As shown, in the desktop telescopic reading and writing device, the top ends of the support plate 3, the plane beam splitter 1, and the concave reflector 2 can be rotatably connected through one or two rotating shafts. In order to adjust the angle of the plane beam splitter 1, the desktop telescopic reading and writing device is also provided with a first adjusting member 13, through which the angle between the plane beam splitter 1 and the concave reflector 2 can be adjusted; one end of the first adjusting member 13 is connected to the plane beam splitter 1, and the other end is connected to the support plate 3 or the concave reflector 2; the first adjusting member 13 can be implemented using a rotating shaft with a limiting mechanism, or it can be an independently provided adjusting member. For example, Figure 4 As shown, a retractable connecting rod is used to adjust the angle between the plane beam splitter 1 and the concave reflecting mirror 2.

[0055] The desktop telephoto reading and writing device can be either a fixed device or a foldable device. In a fixed device, the concave reflector 2 always remains in a fixed horizontal or vertical state, regardless of whether it is in use, and the concave reflector 2 is always perpendicular to the support plate 3. In a foldable device, the concave reflector 2 and / or the support plate 3 are rotatable, so that the concave reflector 2 and the support plate 3 can be switched between mutually parallel and mutually perpendicular states. When the concave reflector 2 and the support plate 3 are mutually parallel, it corresponds to the folded state of the desktop telephoto reading and writing device, i.e., the idle state; when the concave reflector 2 and the support plate 3 are mutually perpendicular, it corresponds to the open state of the desktop telephoto reading and writing device, i.e., the use state. The above state transition can be achieved by a second adjustment member 14, which is used to maintain the concave reflector 2 in a state parallel or perpendicular to the support plate 3. This can be achieved using a rotating shaft with a limit mechanism, or it can be an independently provided adjustment member. For example, both ends of the second adjusting member 14 are connected to the supporting plate 3 and the concave reflecting mirror 2 respectively, and the state of the concave reflecting mirror 2 relative to the supporting plate 3 is switched by the second adjusting member 14 .

[0056] In addition, it can be understood that when the first adjusting member 13 and the second adjusting member 14 are arranged at a position away from the top end of the concave reflecting mirror 2 and the plane beam splitter 1, and only play the role of rotation adjustment and limiting, one or two rotating shafts need to be provided between the plane beam splitter 1, the concave reflecting mirror 2 and the support plate 3 to realize the connection between the three. At this time, the rotating shaft can be a freely rotating movable shaft; when the first adjusting member 13 or the second adjusting member 14 is provided at the end of the concave reflecting mirror 2 and the plane beam splitter 1, and the first adjusting member 13 or the second adjusting member 14 plays the role of connection, rotation adjustment and limiting at the same time, the first adjusting member 13 or the second adjusting member 14 can only use a damping rotating shaft with a limiting mechanism to achieve the above functions. At this time, there is no need to set up a movable shaft separately.

[0057] like Figure 1 and Figure 5 As shown, the desktop telephoto reading and writing device provided by the present invention also has a contrast control function. By arranging a backlight panel 12 on the side of the support plate 3 facing the exit pupil, the contrast control of different areas of the telephoto image can be achieved. The backlight panel 12 includes an array light source. The light of the backlight panel 12 is emitted to the exit pupil position through the plane beam splitter 1. Figure 2 Whether it is the exit pupil position 5 shown in FIG. 1 or the exit pupil position 6 shown in FIG. 3 , the human eye can receive the weak light emitted by the backlight panel 12 when viewing a distant image. By controlling the brightness of different areas of the backlight panel 12 , the contrast of different areas of the distant image can be changed.

[0058] Since the image size of the desktop telephoto reading and writing device is large, the human eye's focus point is variable and does not always converge on the center of the telephoto image. In order to improve the myopia prevention and control effect of contrast control, it is necessary to control the brightness of the local area of ​​the backlight plate 12 in a targeted manner. Figure 1 As shown, in this desktop telephoto reading and writing device, an eye-tracking camera 10 is also positioned facing the eye. For example, the eye-tracking camera 10 is positioned on the upper surface of the plane beam splitter 1 or on the front side of the concave reflector 2, facing the eye when in use. The eye-tracking camera 10 is used to capture images of the eye. An infrared light source in the eye-tracking camera 10 illuminates the eye and provides a corneal reflection point, while a high-speed camera captures eye movements. The eye-tracking camera 10 and the backlight 12 are both electrically connected to a controller 8. Based on the eye image, the controller 8 determines the eye's gaze point in the telephoto image and reduces the brightness of a small area centered on the backlight 12 relative to the gaze point relative to the surrounding area. The "gaze area" refers to this small area centered on the gaze point. The size of the gaze area is determined based on the size of the backlight area corresponding to the eye's small field of view. It should be no larger than the size of the backlight area 12 corresponding to the eye's ±12° field of view, and no smaller than the size of the backlight area 12 corresponding to the eye's ±3° field of view. For example, the controller 8 receives and processes images taken by the eye tracking camera 10, calculates the gaze position, analyzes the data, and then controls the light sources in other areas of the backlight panel 12 except the gaze area (for example, a circular area centered on the gaze point, with a diameter of 6 to 8 cm).

[0059] By controlling the brightness of the backlight panel, low contrast is achieved in the area surrounding the focus area. This reduces or eliminates the brightness of the light source within the focus area and a small surrounding area, while the brightness of the light source in other areas is higher than that of the focus area. This creates a contrast-reduced effect around the focus area, helping to reduce the progression of myopia.

[0060] The lighting control of the gaze area can be achieved by reducing the brightness of the light source in the gaze area or turning off the light source in the gaze area. The brightness of the light source in other peripheral areas of the backlight panel 12 away from the gaze area can be the same as the brightness of the light source in the surrounding area of ​​the gaze area, or lower than the brightness of the light source in the surrounding area of ​​the gaze area, without limitation.

[0061] In this embodiment, the backlight panel 12 can use an LED backlight panel, including an LED array. The distribution of the array light source can refer to Figure 5As shown, the array light source can completely cover the entire area of ​​the backlight panel 12 and be evenly arranged to cover the entire imaging range of the telephoto image. This, combined with eye tracking, allows for targeted control of local areas of the backlight panel 12. To reduce the graininess of the array light source and mitigate the impact of individual LED light sources on imaging quality, a diffuser 11 is installed in the backlight panel 12 in the direction of the array light source's light output. Alternatively, the diffuser can be omitted, resulting in a dotted, low-contrast image surrounding the gaze area.

[0062] like Figure 5 As shown, the distribution of the LED array in the backlight panel 12 can be honeycomb-shaped, with one LED distributed in the center of each hexagon, and the spacing between adjacent LEDs is 5 to 15 mm. The light-emitting surface is covered with a light-homogenizing plate 11 to make the light softer. The distribution of the LED array can also be arranged in other regular or irregular ways. In the direction of the exit pupil, a low-contrast image with high-brightness backlight can be observed outside the non-attention area, and a high-contrast image with low-brightness backlight or no backlight can be observed in the attention area. By controlling the contrast of the peripheral image, the growth of the eye axis can be suppressed.

[0063] The array light source in the backlight panel 1 can also be distributed in a localized manner, such as Figure 6 As shown, the array light source is only set in the peripheral area of ​​the backlight plate 15, thereby increasing the brightness of the peripheral area of ​​the distant image and reducing the contrast, and the brightness of the central area of ​​the distant image is not changed. The array light source can be symmetrically set only in the two side areas of the backlight plate 15, or it can be set at the same time in the entire peripheral area of ​​the backlight plate 15, thereby leaving a central area of ​​a circle, square or other symmetrical shape empty. In addition, the array light source can also be distributed in one or more local areas of the backlight plate 15. The arrangement of the local areas can be regular or irregular, preferably symmetrical about the center of the field of view or the axis of the field of view. In addition, it is also possible to replace the backlight plate with different contrast patterns to achieve the effect of different areas having different contrasts. By replacing different backlight plates, the contrast distribution stimulates the human eye. The backlight plate is replaceable, and the arrangement of the array light sources is different in different backlight plates.

[0064] exist Figure 6 In the embodiment shown, since the light source array in the backlight panel 15 is only provided in the peripheral area, in this embodiment, an eye tracking sensor may not be provided, and all light sources in the peripheral area may be directly illuminated to reduce the contrast of the peripheral area of ​​the distant image, thereby achieving the purpose of inhibiting the growth of the eye axis.

[0065] Contrast can also be achieved by using different forms of backlight panels. For example, the backlight panel includes a fixed white panel that is illuminated as a whole and a dark electrochromic film covering it. The fixed white panel can be installed on a support plate, covered with a dark electrochromic film. The transmittance of the electrochromic film at different positions at different times is controlled by a logic timing circuit to change the brightness of different areas of the backlight panel, thereby forming a constantly changing contrast image in the human eye.

[0066] This desktop telephoto reading and writing device needs to be used in conjunction with a fill light 7. In order to ensure the brightness of the desktop in the area below the plane spectrometer 1, the fill light 7 is set on the frame of the lower surface of the plane spectrometer 1. Preferably, the fill light is composed of a plurality of linearly arranged light sources, and the plurality of light sources are arranged in a stepped manner. The plurality of light sources are arranged along the length direction of the plane spectrometer 1, and when the plane spectrometer 1 and the desktop are in use at a 45° angle, the main light of each light source is vertically downwardly projected toward the desktop. In order to meet the uniformity of the illumination of the desktop, the number of light sources distributed above can be greater than the number of light sources below, and the arrangement can be dense. The fill light 7 is preferably set on the left and right frames of the lower surface of the plane spectrometer 1. The fill light 7 can also be set on the bottom frame of the plane spectrometer 1 and on the bottom surface of the support plate 3 at the same time, so as to provide light source to the desktop at the same time.

[0067] The present invention also provides a control method for a desktop telescopic reading and writing device, wherein light reflected by a desktop 4 and an object placed on the desktop is directed from below toward a plane beam splitter 1, the light split by the plane beam splitter 1 is directed toward a concave reflector 2, and then, after being reflected by the concave reflector 2 and split by the plane beam splitter 1, is directed toward an exit pupil position and forms a telescopic image at a position not less than 3 meters; at the same time, a backlight panel 12 is arranged facing the exit pupil position and has different brightness in different areas, thereby changing the contrast of different areas of the telescopic image to achieve contrast control.

[0068] In a preferred embodiment, the illuminated area of ​​the backlight panel 12 changes based on the position of the eye's gaze point. The controller 8 determines the eye's gaze point in a distant image in real time based on the eye image and sets the brightness of the light source in a small area of ​​the backlight panel 12 centered on the gaze point to be lower than the brightness of the light source in the surrounding area. The "gaze area" refers to this small area centered on the gaze point. The size of the gaze area is determined based on the size of the backlight panel corresponding to the eye's narrow field of view. It should be no larger than the size of the area of ​​the backlight panel 12 corresponding to the eye's ±12° field of view, and no smaller than the size of the area of ​​the backlight panel 12 corresponding to the eye's ±3° field of view. For example, the controller 8 receives and processes images captured by the eye-tracking camera 10, calculates the gaze position, analyzes the data, and then controls the light source in the backlight panel 12 except for the gaze area (e.g., a circular area with a diameter of 6 to 8 cm centered on the gaze point) to illuminate, turning off the light source in the gaze area. The brightness of the light source in areas outside the gaze area can be increased in a stepped manner centered on the gaze point. Of course, the controller 8 can also make the entire backlight panel centered on the gaze point, with the brightness gradually increasing from the center to the outside, thereby replacing the above-mentioned on-off brightness control, wherein the ratio of the average brightness of the gaze area to the average brightness of the surrounding area should be lower than 40%.

[0069] By controlling the brightness of the backlight panel, the contrast around the focus area is reduced. This reduces the brightness of the area of ​​focus and a small surrounding area, while the brightness of other areas is higher than the focus area. This creates a contrast-reduced effect around the focus area, helping to reduce the progression of myopia.

[0070] In summary, the desktop telephoto reading and writing device with contrast control provided by the present invention utilizes a Birdbath coaxial optical system to magnify and project distant images of objects such as books placed on a tabletop, achieving an imaging effect similar to that of a telescope. This structure achieves a nearly distortion-free, high-definition image without the introduction of free-form surfaces, while also reducing the difficulty of processing and assembly. Furthermore, the desktop telephoto reading and writing device also incorporates contrast control. When the user is viewing text or other content in a book, the image contrast outside the gaze area is reduced, inhibiting the growth of the eye axis and potentially having a certain effect on choroidal thickening, thereby achieving myopia prevention and control.

[0071] The above describes in detail the desktop telephoto reading and writing device with contrast control and its control method provided by the present invention. For those skilled in the art, any obvious modification made to the present invention without departing from the essence of the present invention will constitute an infringement of the patent rights of the present invention and will result in corresponding legal liability.

Claims

1. A desktop telescopic reading and writing device with contrast control, characterized in that: include: A plane beam splitter, a concave reflector and a backlight plate; wherein, The concave reflector is kept in a horizontal or vertical position when in use; the plane beam splitter is tilted when in use; The backlight plate and the concave reflector are arranged perpendicular to each other and are used to provide light to the exit pupil position; The light reflected by the desktop and the objects placed on the desktop is directed toward the plane beam splitter from below, and the light formed after the beam splitting by the concave reflector is reflected by the concave reflector, and then is directed toward the exit pupil position after the beam splitting by the plane beam splitter, and forms a distant image at a position not less than 3 meters; the brightness of different areas of the backlight panel is different, so as to change the contrast of different areas of the distant image.

2. The desktop telescopic reading and writing device as claimed in claim 1, characterized in that Also included is an eye-tracking camera and controller; The eye tracking camera is arranged facing the exit pupil position and is used to collect images of human eyes; The controller determines the gaze point of the human eye in the distant image according to the human eye image, and makes the brightness of the gaze area centered on the gaze point in the backlight plate lower than the brightness of the area around the gaze area.

3. The desktop telescopic reading and writing device according to claim 2, characterized in that: In the backlight panel, the array light source covers the entire area of ​​the backlight panel, and the controller makes the light source in the focus area have low brightness or does not emit light.

4. The desktop telescopic reading and writing device according to claim 2, characterized in that: The backlight panel includes a fixed white panel and a dark electrochromic film covering the fixed white panel. The transmittance of the electrochromic film at different positions at different times is controlled by a logic timing circuit to change the brightness of different areas of the backlight panel.

5. The desktop telescopic reading and writing device according to claim 1, characterized in that: In the backlight panel, the array light sources are distributed only in the peripheral area of ​​the backlight panel, or only in one or more local areas.

6. The desktop telescopic reading and writing device according to claim 5, characterized in that: The backlight panel is replaceable, and the array light sources are arranged differently in different backlight panels.

7. The desktop telescopic reading and writing device according to claim 1, characterized in that: Also includes: The first adjusting member is used to adjust the angle between the plane beam splitter and the concave reflecting mirror, and to keep the plane beam splitter at at least two positions where the angle between the plane beam splitter and the concave reflecting mirror is between 30° and 60°; the angle between the plane beam splitter and the concave reflecting mirror is adjusted by the first adjusting member to change the height of the exit pupil position relative to the desktop.

8. The desktop telescopic reading and writing device as claimed in claim 1, characterized in that Also includes: The fill light is arranged on the lower surface of the plane beam splitter, and the fill light is composed of a plurality of light sources arranged linearly, the plurality of light sources are arranged in a stepped manner, and when the plane beam splitter and the desktop are in a use state with an angle of 45 degrees, the main light of each light source is perpendicular to the desktop.

9. A control method for a desktop telescopic reading and writing device, characterized in that The steps include: The desktop telescopic reading and writing device comprises: a plane beam splitter, a concave reflector and a backlight plate; wherein, The light reflected by the desktop and the objects placed on the desktop is directed toward the plane beam splitter from below, and the light formed after the beam splitting by the concave reflector is reflected by the concave reflector, and then is directed toward the exit pupil position after the beam splitting by the plane beam splitter, and forms a distant image at a position not less than 3 meters; the backlight panel is arranged facing the exit pupil position and the brightness of different areas is different, so as to change the contrast of different areas of the distant image.

10. The control method of the desktop telescopic reading and writing device according to claim 9, characterized in that: Use eye tracking camera to collect human eye images; The controller determines the gaze point of the human eye in the distant image according to the human eye image, and makes the brightness of the gaze area centered on the gaze point in the backlight panel lower than the brightness of the surrounding area of ​​the gaze area.

11. The control method of the desktop telescopic reading and writing device according to claim 10, characterized in that: The range of the gaze area is not larger than the size of the area in the backlight panel corresponding to the ±12° visual field of the human eye, and is not smaller than the size of the area in the backlight panel corresponding to the ±3° visual field of the human eye.

12. The control method of the desktop telescopic reading and writing device according to claim 10, characterized in that: The range of the gaze area is a circular area centered on the gaze point, and the diameter of the circular area is 6 to 8 centimeters.

13. The control method of the desktop telescopic reading and writing device according to claim 10, characterized in that: The brightness of the area outside the fixation area increases in steps with the fixation point as the center.

14. The control method of the desktop telescopic reading and writing device according to claim 10, characterized in that: The entire backlight panel is centered on the gaze point and the brightness gradually increases from the center to the outside.

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