WO2007068189A1

WO2007068189A1 - An optical imaging apparatus of an optical mouse

Info

Publication number: WO2007068189A1
Application number: PCT/CN2006/003332
Authority: WO
Inventors: Shilin Deng
Original assignee: Shilin Deng
Priority date: 2005-12-13
Filing date: 2006-12-08
Publication date: 2007-06-21
Also published as: CN1983140A

Abstract

An optical imaging apparatus of an optical mouse includes two or more lens light paths (A), the beams reflected by a work surface (4) form the images and superpose on a photosensitive surface of a image sensor (1) through corresponding different lens light paths (A). The above each lens path (A) corresponds to respective different special effective depth of focus section, the special effective depth of focus sections of the different lens light paths mutually extend on the optical axis and form the obviously extended effective depth of focus as a whole above the effective depth of focus of a single lens light path; of the above two or more superposed image within the total effective depth of focus range, at least one light path forms a relatively clear image, the image superposes a clear or blurry image formed by the other light paths on the photosensitive surface of the image sensor (1).

Description

Optical imaging device for optical mouse

The present invention is an optical imaging device for an optical mouse, and more particularly to a multi-lens optical path optical imaging device suitable for a pen-shaped optical mouse. It belongs to the transformation technology of optical imaging devices used in optical mice.

Background technique

In the existing optical mouse, since the object distance is relatively stable during use, most of the optical imaging devices with smaller effective depth of field are used. The principle of such an optical mouse is disclosed in U.S. Patent No. 6,233,368, the entire disclosure of which is incorporated herein by reference. In this patent, an illuminator housed in an optical mouse illuminates a work surface disposed directly beneath the optical mouse, and an imaging system mounted therein images any pattern or feature of the work surface on the light-sensing surface of the CMOS sensor. Since the mouse is in direct contact with the work surface during operation, the working surface is fixed at a distance from the imaging device, and a conventional optical imaging lens can be used to maintain clear imaging.

Since the shape of the mouse is different from that of a normal writing tool, it is necessary to operate the entire mouse in the hand, so it is difficult to implement writing and drawing operations. A pen-shaped mouse device has been developed which enables precise cursor control and simple writing when performing precise drawing operations or writing. An example of such a pen-shaped mouse is disclosed in U.S. Patent No. 6,151,015 issued to November 21, 2000, entitled "Pen-like Computer Indicating Device". As shown in FIG. 1, the pointing device includes a cylinder 102, an illumination source 104, a lens 110, an optical movement sensor 108, a switch 106, communication links 116 and 118, and buttons 112 and 114. The illuminating light source 104 emits light, and the lens 110 images the light reflected from the working surface on the optical movement sensor 108. Thus, when the optical movement sensor 108 captures an image of the work surface imaged by the lens 110, the direction of motion and the amount of motion of the pointing device can be obtained from changes in the image. The optical imaging device of the patent has a large disadvantage in drawing or writing. When the distance between the pointing device and the working surface fluctuates greatly, the working surface is on the image sensor due to the effective depth of field limitation of the conventional mouse optical imaging system. The imaging is poorly blurred, which affects the capture of the image by the sensor. Referring to Fig. 4 for the input of the character "X", the operation of the pen is usually composed of a combination of a pen down motion and a pen lift motion. In Figure 4, when the letter "X" is written, the writing action consists of the following steps: 1. Step Ml: Write the pen at a specific point, then write "/,,; 2. Step M ² : Lift the pen, then in the air a clockwise arc; three steps

Confirmation Step M3: Write a pen at a specific point, write "\", and then lift the pen. Throughout the writing process, both the pen and the pen require the pen mouse to maintain precise positioning. Usually, the distance separating from the working surface in the lifting action varies depending on the usage habits of different people, generally less than 12 mm.

In order to make the pen-shaped optical mouse device smoothly focus when it comes into contact with the working surface or away from a working distance, so that it can correctly determine the moving direction and distance of the mouse, thereby enabling smooth writing or drawing, which has been developed by the industry. A pen-shaped mouse device: the telecentric optical system or the variable-focus lens group is used to increase the effective depth of field of the optical imaging lens system. For example, Chinese Patent Application No. 01802379. 7 discloses a pen-shaped optical mouse device and a control method thereof. " (Public Date: January 1, 2003), its schematic diagram is shown in Figure 2. It has made some useful improvements, including the telecentric optical imaging system shown in Figure 3. In the figure, 10, main body, 11, illumination unit, 12, light guide, 13, imaging system, 13a, convex lens, 13b, mirror, 14, image sensor, 15, control device, 16, transmission device, 17, setting button , 18, moving wheel switch, 19, contact sensing equipment, 20, working surface. Due to the use of the telecentric optical system, the object distance of the lens is relatively long, which increases the effective depth of field of the lens system, and the pen mouse can form a clear image when it is in contact with the working surface or moves within a certain distance. . However, due to the different writing habits or application range of each person, the distance of the pen mouse from the working surface is different when moving in the air, which requires a large effective depth of field (about 6 to 12 mm) to meet the practical application. Due to the limitation of single-lens optical path single focal length optical system, the longer the effective depth of field, the longer the object distance requirement of the lens optical path, the greater the ratio of the object distance to the diameter of the lens, and the lower the light efficiency of lens imaging. It is difficult for an imaging lens to achieve sufficient effective depth of field and desired light efficiency in a small space of a pen mouse. However, if a zoomable optical imaging system is used, it is necessary to dynamically adjust the focal length of the lens group or dynamically adjust the distance between the lens and the image sensor, which requires an increase in the distance measuring device and the driving device, which greatly increases the design difficulty and the manufacturing cost.

The imaging system of the existing single lens optical path single focal length convex lens is shown in FIG. 5, in the figure, 1. image sensor, 2. processing control unit, 3. imaging lens, 4. working surface. The schematic diagram of its imaging situation is shown in Figure 11, and the working surface can be clearly imaged within its effective depth of field range h. In the figure, when the work surface is at a. At the time of the scene, the point on the working surface (the point is a black point on a white background on the working surface, see Fig. 15) is a clear image formed on the image sensor S as shown in Fig. 16, and its multiple phases The adjacent dots form a clear image on the light sensing surface S of the image sensor as shown in FIG. When the work surface is made of a. At the X direction of the optical axis of the lens When moving everywhere, the point on the working surface forms a blurred image on the light sensing surface S' of the image sensor. As shown in FIG. 17, a plurality of adjacent points are formed on the light sensing surface S of the image sensor. The blurred image is shown in Fig. 19, and it is difficult for the image sensor to capture the motion state of the image.

Summary of the invention

The object of the present invention is to provide a method capable of being installed in a small volume of a pen-shaped mouse and providing a large effective depth of field for the above problem, so that the image sensor can correctly capture the movement of the image when the pen-shaped mouse is smoothly written or drawn. Optical imaging device for optical mouse with direction and distance.

A schematic structural view of the present invention is shown in FIG. 6 and includes two or more lens optical paths (A), and the light reflected by the working surface (4) passes through the corresponding different lens optical paths (A) in the image sensor (1). Images are formed on the light sensing surface and superimposed.

Each of the lens optical paths (A) corresponds to a different unique effective depth of field segment, and the unique effective depth of field segments of the different lens paths continue in the optical axis direction to form an effective effective depth of field which is substantially longer than the effective depth of field of the single lens optical path; The above two or more overlapping images have at least one optical path in the overall effective depth of field to form a clear image, which is formed with other optical paths or blurred or clear images in the image sensor (1) The sensing surfaces overlap.

When the above working surface (4) moves laterally relative to the optical axis direction within the overall effective depth of field, there is always an effective depth of field corresponding to the position of the working surface (4), and the light reflected by the working surface (4) passes through The lens light path (A) corresponding to the effective depth of field segment can form a clear image on the light sensing surface of the image sensor (1); each lens light path) forms an image independently of each other, and each image thereof is in the image sensor' ( 1) The light-sensing surface is superimposed to form an overlapping image for the processing control unit (2) for comparison processing and positioning.

The lens optical path (A) is a focusing lens optical path including a convex lens (3); each lens optical path is a focusing lens optical path composed of one or more convex lenses and/or concave lenses, prisms, and mirrors; When the acre is located above the lens group, in the direction of the optical axis, the focusing lens groups of different focal lengths constituting the optical paths of the respective focusing lenses are adjusted from top to bottom in accordance with the focal length from long to short.

The convex lenses (3) of the above-mentioned respective lens optical paths have different focal lengths; the optical axes of the respective convex lenses (3) may coincide or separate; and each convex lens (3) is on the same optical plane. .

The convex lens includes a spherical convex lens and an aspherical convex lens, and the concave lens includes a spherical concave surface Mirror and aspherical concave lenses, the mirrors comprising a common mirror and a mirror prism. When the above working surface (4) moves laterally relative to the optical axis direction within the overall effective depth of field, there will always be an effective depth of field corresponding to the position of the working surface (4), and the light reflected by the working surface (4) passes through The lens light path (A) corresponding to the effective depth of field segment can form a clear image on the light sensing surface of the image sensor (1); each lens light path (A) forms an image independently of each other, and each image thereof is in the image sensor. The light-sensing surface of '(1) is superimposed to form an overlapping image for the processing control unit (2) for comparison processing and positioning.

In the present invention, since the light path including two or more parallel lens optical paths is used, the light reflected by the working surface forms an image on the light sensing surface of the image sensor through the corresponding different optical paths and is superimposed, and each lens light path corresponds to each other. The unique effective depth of field segment enables the unique effective depth of field segments of the different lens paths to continue in the direction of the optical axis to form an overall effective depth of field, thereby making the overall effective depth of field significantly longer than the effective depth of field of a single lens path. In the pen-shaped optical mouse, the optical imaging device of the present invention is used, when the pen-shaped mouse is in contact with the working surface, that is, the working surface is located in the overall effective depth of field, and a portion of the lens group has a unique effective depth of field, and at this time, the light reflected from the working surface The lens light path corresponding to the unique effective depth of field segment can form a clear image on the light sensing surface of the image sensor, and the light reflected by the working surface passes through the image formed by the other lens light path on the light sensing surface or Clear or fuzzy. Clear and blurred images overlap on the light-sensitive surface to form a special overlapping image. The image sensor and its processing control unit continuously capture and compare the displacement of the image in a short period of time, and the moving state of the image can be obtained. The same principle, when the pen mouse is at a certain distance from the working surface, the pen movement is performed, and the working surface is located in a corresponding effective depth of field segment corresponding to the set effective effective depth of field. At this time, the working surface reflects The light path of the lens corresponding to the unique effective depth of field segment forms a clearer image on the light-sensing surface, and the light reflected by the working surface passes through the path of the other lens to form a clear or blurred image on the light-sensing surface. Clear and blurred images overlap on the light-sensitive surface to form a special overlay image. Through the image sensor and its processing control unit continuously capture and compare the displacement of the image in a short period of time, the moving state of the image can be obtained, thereby obtaining the moving state of the mouse. In this way, as long as the working surface is within the effective effective depth of field in the direction of the optical axis, there is always a unique effective depth of field segment corresponding to the position of the working surface in the overall effective depth of field, and the light reflected by the working surface passes through A corresponding lens path of an effective depth of field can always form a clear shadow on the light sensing surface. Like, the image reflected by the working surface passes through other lens paths to form an image on the light-sensing surface that is either clear or blurred. The invention is ingeniously designed, and is an optical imaging device for a pen-shaped optical mouse which is effective and convenient to use.

DRAWINGS

Figure 1 is a schematic view showing the structure of a "computer-like pointing device similar to a pen" of U.S. Patent No. 6,051,015;

Figure 2 is a schematic view showing the structure of a pen-shaped mouse named "Pen-shaped optical mouse device and its control method" in Chinese Patent Application No. 01802379.

Figure 3 is a schematic diagram of a telecentric optical system named "Pen-shaped optical mouse device and its control method" in Chinese Patent Application No. 01802379.

Figure 4 is a diagram showing the steps of writing the letter "X";

Figure 5 is a schematic view showing the imaging of a single lens optical path single focal length imaging device;

6 is a schematic view of Embodiment 1 of the present invention, in which three optical axes of different focal lengths coincide, and three convex lenses are arranged concentrically on the same optical plane, and the effective depth of field of the lens paths of three different focal lengths is The optical axes continue each other;

7 is a schematic view of Embodiment 1 of the present invention, wherein the focusing convex lens is independently imaged by two lenses, and the image is superimposed on the light sensing surface by a mirror or a reflecting prism, and the optical axes of the respective convex lenses are separated; FIG. 8 is the present invention. A schematic diagram of Embodiment 3, wherein the optical axes of the convex lenses of the three different focal lengths are the same, and the lens is viewed from above the optical axis to the lens group, and the lens is arranged concentrically with the focal length from the longest to the shortest from the inside to the outside.

Figure 9 is a schematic view of Embodiment 4 of the present invention, wherein three convex lenses are superimposed from top to bottom, and the optical axes of the respective convex lenses are coincident, and the effective depth of field of the three lens paths continues on the optical axis; Figure 10 is A schematic diagram of Embodiment 5 of the present invention, which uses a single-sided convex lens, and three different focal lengths of convex lenses have the same optical axis and are layered from top to bottom and arranged concentrically around the optical axis;

Fig. 11 is a schematic diagram showing the imaging situation of the working faces of the single focal length optical imaging device at different positions. When the working surface can only be changed within a small effective depth of field, a clearer image can be obtained on the light sensing surface;

Figure 12 is the same optical axis of the three convex lenses of different focal lengths in the multi-lens optical path optical imaging device In the same optical plane, the working surface is within the overall effective depth of field, and the light reflected by the working surface is imaged by the lens optical path of different focal lengths on the light sensing surface of the image sensor. In the figure, the light reflected by the working surface can form a clear image on the light-sensing surface of the image sensor only through the lens light path corresponding to the working surface, and the image formed by the other lens light path is blurred;

Figure 13 is a view showing that the optical axes of the two convex lenses of different focal lengths in the multi-lens optical path optical imaging apparatus are the same and on the same optical plane. When the working surface is located at different distances from the lens on the optical axis, that is, when the object distance is different, the light reflected by the working surface is clearly imaged by the lens optical path of different focal lengths corresponding to the lens on the light sensing surface. There are significant differences in image size;

14 is a multi-lens optical path optical imaging device in which the position of two different focal length imaging convex lenses is adjusted according to the ratio of the object distance/image distance, and when the working surface is located at different distances from the lens on the optical axis, the light reflected by the working surface passes through The schematic diagram of the corresponding lens optical path with different focal lengths on the light-sensing surface is clearly imaged, and the adjusted image size is not different;

Figure 15 is a black dot on a white background on the work surface;

Figure 16 is a clear image of a black spot on a white background on a work surface formed on a light-sensing surface through a lens path;

Figure 17 is a blurred image of a black spot on a white background on a work surface formed on a light-sensing surface through a lens optical path;

Figure 18 is an image of a black spot on a white background on a work surface formed by a plurality of lens paths of different effective depths of view on the light-sensing surface, and an image formed by overlapping a clear image and some blurred images;

Figure 19 is a blurred image of four adjacent black spots on a white background on a work surface formed on a light-sensitive surface through a lens optical path;

Figure 20 is a view showing four adjacent black spots on a white background on a working surface through a plurality of lens paths of different effective depths of field forming an image on the light sensing surface, wherein the clear image of the four points and the blurred image are overlapped. Image

Figure 21 is a clear image of four adjacent black spots on a white background on the working surface formed by a lens on the light sensing surface;

Figure 22 is a partial example of the optical axis of each lens of the multi-lens optical path optical imaging device. a top view of the mirror group;

Figure 23 is a plan view showing the arrangement of the improved lens optical path. In the top view, one of the convex lenses in the five lens optical paths is circular in the middle, and the other four are located around the circumference, forming an annular shape; A top view of a modified lens path arrangement in which the convex lenses in the four lens paths are equally divided into four, each occupying a quarter circle.

Figure 25 is a view showing that the optical axes of the two convex lenses of different focal lengths in the multi-lens optical path optical imaging apparatus are the same and on the same optical plane. The working surface is located at the effective depth of field intersection of the two lens paths. When the working surface moves in a direction perpendicular to the optical axis, the light reflected by the working surface is formed by the different lens optical paths on the light sensing surface of the image sensor. A schematic diagram of different moving speeds;

26 is a view showing that the optical axes of the two convex lenses of different focal lengths are the same in the multi-lens optical path optical imaging device, and the distance between each lens and the light-sensing surface of the image sensor is adjusted, and the focus between the lens group and the light-sensing surface is coincident on the optical axis. The working surface is located at the effective depth of field intersection of the two lens optical paths. When the working surface moves in a direction perpendicular to the optical axis, the light reflected by the working surface is formed on the light sensing surface of the image sensor by different lens optical paths with similar sharpness. a schematic diagram of the same speed of movement;

Figure 27 is a schematic view of Embodiment 6 of the present invention.

detailed description

Example 1:

Due to the imaging characteristics of the spherical convex lens, the following embodiments are mainly described by a spherical convex lens for convenience of explanation and drawing.

Figure 6 is a schematic illustration of one embodiment of a multi-lens optical path optical imaging device. It uses three lens optical paths, the convex lenses (3) of the respective lens optical paths have different focal lengths and the optical axes coincide, and the three convex lenses (3) are arranged concentrically in the same optical plane from short to long from the inside to the outside. , as shown in Figure 23. The effective depth of field segments corresponding to the lens paths of different focal lengths are mutually extended from the top to the bottom on the optical axis to form a long overall effective depth of field. In Figure 6, H ₂ H ₃ is the effective depth of field corresponding to the lens paths of three different focal lengths from the inside to the outside in the lens group, and the three effective depth of field segments of H ₂ and H ₃ are mutually extended, so that the overall effective depth of field is more effective than the single effective depth of field. The depth of field segment is significantly extended. In order to ensure that the working surface moves in the direction of the optical axis in the overall effective depth of field and has a clear image, the three effective depth of field segments of ^, H ₂ . H ₃ partially overlap each other. In the illustrated embodiment, the lens path refers to light passing through one or a group of identical lenses. The general term for the route, each lens path has a different focal length and effective depth of field segment. The effective depth of field means that in the optical lens imaging device, in the direction of the optical axis, the light reflected by the object or pattern located thereon can form a desired clear image through the position of the optical path of the lens on the optical axis. A continuous segment of position in the direction of the optical axis. Here, the unique effective depth of field segment of each lens optical path means that light reflected by the working surface located within the effective depth of field segment can be formed on the light sensing surface of the image sensor through the corresponding lens optical path. A segment of continuous position of the sharper image in the direction of the optical axis.

In Fig. 6, when the working surface (4) is located within the effective depth of field within the overall effective depth of field, the working surface (4) is located at a. At the time, the light reflected by the working surface (4) forms a clear image on the light sensing surface of the image sensor (1) through the lens optical path corresponding to the effective depth of field segment, and corresponds to the effective depth of field segments h ₂ and h ₃ . The image formed by the lens path is blurred. When the effective depth h inside face section (4) is located generally effective depth of field of _3, i.e. the face (4) it is located at the _ai, reflected light passes through the lens face with the optical path corresponding to the effective depth of field of the image sensor section ( 1) A clear image is formed on the light-sensing surface, and the image formed by the optical path corresponding to the effective depth of field and corresponding lens is blurred. The images formed by the different lens paths described above overlap on the light-sensing surface of the image sensor (1) to form a special superimposed image.

Figure 12 is a multi-lens optical path optical imaging device in which the optical axes of the three convex lenses of different focal lengths are the same and on the same optical plane, the working surface is within the overall effective depth of field, and the light reflected by the working surface passes through the lens optical path of different focal lengths in the image sensor. Schematic diagram of the imaging situation on the light-sensing surface. In the figure, the light reflected by the working surface can only form a clear image on the light-sensing surface of the image sensor through the lens light path that is adapted to it, and the image formed by the other lens light path is blurred. In the figure, the working surface is located on the effective depth of field segment 11 ₂ within the effective effective depth of field, the focal point of the lens optical path corresponding to the effective depth of field segment h ₂ is e ₂ , and the light reflected by the point a on the working surface passes through the lens with the focus of _ei an optical path between the light sensitive surface of the image sensor focus e _t capable of forming a clear image, for the image formed on the light-sensing surface S blur on the image sensor. The image formed at this time is as shown in FIG. 17 , which is a circular or annular image formed on the light-sensing surface S by a black dot on the white background of the working surface ( FIG. 15 ) (specifically, the convex lens is passed through). The shapes are different and different. For the convenience of drawing and illustration, the figure is illustrated in a circular pattern. And the light reflected by the point a on the working surface passes through the lens optical path with the focus of 6 ₂ to form a clear on the light sensing surface. The image is b ₂ . The image formed by it is shown in Fig. 16, which is a clear image formed on the light sensing surface S by a black dot on the working surface on a white background (Fig. 15). A point light reflected from the working surface through the focal point of the optical path 6 b ₃ lens ₃ can form a clear image on the right side of the light sensing surface S, the image formed on the light sensing surface S blur. The image formed by it is shown in Fig. 17, which is a circular or circular image formed on the photosensitive surface S by a black dot on the white background of the working surface (Fig. 15). The light reflected by a black dot a on a white background of the working surface is superimposed on the light sensing surface S by three different focal length lens paths of the focal points _ei , e ₂ , ^ to form a superimposed image of the special beads. As shown in Figure 18. Figure 20 is a special overlay image of the four black dots on the white background of the working surface formed by the multi-focus multi-effective effective depth of field lens imaging device on the light sensing surface S of the image sensor, in which four clear 'points are shown A special overlay of the image and the blurred patchy 3⁄4 image. When the working surface is laterally moved relative to the optical axis of the lens within the overall effective depth of field, the moving direction and distance of the working surface can be detected by continuously comparing the overlapping images (the existing optical mouse is about 1500 frames/second).

In the embodiment of Fig. 6, three lens optical paths are employed, and the effective depth of field sections of the three lens optical paths, H ₂ , H ₃ continue on the optical axis, and the working surface is reflected when the working surface is within the effective effective depth of field thereof. The light formed by the lens path of different focal lengths on the light-sensing surface has at least one clear image overlapped with other or blurred or clear images.

As can be seen from the above description, the multi-lens optical optical imaging device of Figure 6 can provide a much larger effective depth of field in a similar volume than conventional single-lens optical path optical devices (Fig. 5).

Since the multi-lens optical path optical imaging apparatus uses two or more lens optical path imaging, and its imaging overlaps on the light sensing surface of the image sensor, it has the following four related problems, and the following four existing embodiments 1 exist. The problem and its solution are briefly analyzed separately.

1. Problem 1: The image formed by the multi-lens optical path optical imaging device on the image sensor is a special image with at least one clear image and other overlapping or blurred images, as shown in Fig. 20. The single-lens optical path optical imaging device has only one clear image when it is clearly imaged, as shown in Figure 21. Therefore, the contrast of the image formed by the multi-lens optical path imaging device with respect to the image formed by the single-lens optical path imaging device is reduced, making the imaging process of the multi-lens optical path optical imaging device more difficult, and in order to solve this problem, Use the following three methods: ^ to improve:

1 Method 1: Improve the sensitivity of the optical motion sensor to image contrast and use an image processing algorithm that is suitable for it to better handle low-contrast images. 2 Method 2: Improve the graphic features of the working surface (such as using a dedicated mouse pad) and improve the illumination of the working surface, so that the light reflected by the working surface forms a clearer image on the light-sensing surface of the image sensor.

3 Method 3: Install a distance measuring device (not shown) on the pen mouse or use a switch or pressure sensor placed on the pen tip to dynamically detect the distance between the working surface and the lens, so that it cannot be clear on the light sensing surface. The optical path of the imaged lens is blocked by an optical switch (such as a liquid crystal optical switch, etc.), and only the optical path of the lens that can be clearly imaged on the light-sensing surface is opened, thereby reducing the blurring of the imaged light. This method can significantly improve the quality of the image, but it will increase the design difficulty and production cost.

2. Problem 2: In the embodiment shown in Fig. 6, the convex lenses of different focal lengths are arranged concentrically from the inside to the outside in the same optical plane, as shown in Fig. 22. In Fig. 13, the optical planes of the two convex lenses are the same as the optical axis, and the working surface is located within the effective effective depth of field. When the working surface is at a different distance from the lens in the optical axis direction, the light reflected by the working surface passes through the position where it is located. The schematic diagram of the case where the corresponding lens path of the effective depth of field segment is clearly imaged on the light-sensing surface of the image sensor, the image size in the figure is significantly different.

Definition: object distance / , image distance 1, the size of the working surface image a, the image size b on the light sensing surface; the formula available from Fig. 13: a / b = / eight; therefore, when the image distance 1, the working surface When the size a of the image remains unchanged, the object distance/larger, the smaller the image size b on the light-sensing surface, the larger the object distance and the smaller the imaging. This results in a significant difference in the size of the image formed by the working surface on the light-sensing surface of the image sensor when the pen-shaped mouse is moved or drawn at a different distance from the working surface, resulting in a pen-shaped mouse at a different distance from the working surface. When the same distance is moved horizontally along the work surface, the amount of movement detected by the pen mouse is different. To reduce this difference, the following methods can be used to improve:

1 Method 1: Adjust the distance between the convex lens of the different lens optical path and the image sensor. According to the formula: a / b = / / 1 ; To keep a / b unchanged, / / 1 also remains unchanged, the working surface from a. When moving to the _ai , the object distance/increase at this time, so that the image is kept constant, the image distance is also increased. As shown in Fig. 14, the convex lens of the lens optical path corresponding thereto is taken from I. Adjust to L, and make the focal length of the lens fit, so aa^ lv^, / D/l / l^ a^bn- ai/b Therefore, by moving the lens with a longer focal length along the optical axis By setting it at an appropriate position farther from the image sensor, it is possible to reduce the difference in image size formed by the working face at different distances from the lens group. 'In addition, after the above adjustment, when the working surface moves laterally from the lens at a certain distance relative to the optical axis direction, the moving distance of the image reflected on the image sensor by the light reflected by the working surface through different lens optical paths will still be different. This requires image transmission The sensor's processing control algorithm is optimized for it.

2 Method 2: Use a pressure sensor or switch (not shown) on the head of the pen mouse to detect the contact between the mouse and the working surface. The working surface is on the image sensor according to the contact and separation between the mouse and the working surface. The difference in imaging size, combined with the user's usage habits (including statistical data and the user's personalized input data), is adjusted by appropriate algorithms to reduce the difference in mouse positioning. This method can also be used in conjunction with method one to reduce the adjustment amplitude of the position of a pair of lenses in the method to control the positioning difference within the permissible range.

3 Method 3: When the lens imaging device with a larger object distance is used to move the same distance longitudinally along the optical axis direction, the ratio of the moving object distance to the original object distance is reduced, thereby forming the working surface on the light sensing surface. The change in image size is reduced. Applying this method will reduce the light efficiency of the lens and increase the volume occupied by the lens group and the optical path.

4 Method 4: By setting a distance measuring device (not shown) on the mouse, it is used to measure the distance between the pen mouse and the working surface, and calculate the difference in imaging size according to the ratio of the object distance/image distance, and adopt an appropriate algorithm. Make adjustments. This method can be used to accurately calibrate the difference in its positioning, but its design difficulty and production cost will be significantly improved.

3. Problem 3: When the working surface moves laterally with respect to the vertical direction of the optical axis, the image reflected by the working surface through the different lens optical paths on the image sensor light sensing surface is different due to the moving speed, so that the processing unit of the mouse overlaps the image. The extraction of mobile information becomes more difficult. In the embodiment shown in FIG. 6, among the three different lens optical paths, the convex lenses of different focal lengths are arranged concentrically from the inside to the outside on the same optical plane, as shown in FIG. 22, and the working surface is located at the effective depth of field of a certain lens path. At a certain position, the light reflected by the working surface can form the clearest image on the light sensing surface of the image sensor through the optical path of the lens, and the image formed by the light of other different lens paths on the light sensing surface is blurred and blurred. The image and the clear image have a large difference in the speed of movement, but the blurred image has little effect on the capture of the moving information of the image processing unit of the mouse to extract the clear image. In Fig. 25, the optical planes of the two convex lenses are the same as the optical axis, i.e., I. , ^ is in the same plane, when the working surface is at the depth of field plane where the point at is located, the light reflected by the working surface can form a clear image on the light sensing surface S of the image sensor through the lens Io (corresponding to the focus is e.) When the working surface is at the depth of field where the point & ₂ is located, the light reflected by the working surface can pass through the lens ^ (the corresponding focus is to form a clear image on the light sensing surface S- of the image sensor, when the working surface is along the lens light When the axial direction a ₂ moves, the working surface reflects Light passes through the lens I. The image formed on the light-sensing surface s of the image sensor is blurred by a clear gradation, and the image formed on the light-sensing surface S of the image sensor through the lens L is sharply blurred by blur. Point a. The working surface is located in the lens I. The point on the work surface when the boundary with the effective depth of field of I is at this point, point a. The reflected light passes through the lens I, respectively. And an image b formed on the light sensing surface S of the image sensor. The sharpness is similar to 1^ (indicated by a circle in the figure, the sharpness is represented by the diameter of the circle, and the smaller the diameter, the higher the definition). When point a. When moving in the vertical direction with the optical axis, the light reflected by the point a passes through the lens I, respectively. And L form images W and b/ of similar sharpness on the light sensing surface S of the image sensor. It can be seen from Fig. 25 that 1„ is b. The moving distance to b is the moving distance of bi gij b/. At this time, G ₀ < G ₁ , > l _la can be seen, the vertical direction of the working surface relative to the optical axis When moving laterally, the light reflected by the working surface is different in the imaging moving speed of the image sensor on the light-sensing surface of the image sensor. When the object lens, the image distance is fixed, and the focal lengths of different focal lengths are on the same plane, the light reflected by the working surface passes through The imaging moving speed of the different lens optical paths on the light sensing surface of the image sensor is inversely proportional to the focal length of the lens.

In order to solve the problem that the moving speed of the image formed on the light-sensing surface of the image sensor on the working surface of the effective depth of field interface is different, according to the optical imaging characteristics of the convex lens, as shown in FIG. 26, the lens and the optical path of each lens are adjusted. The distance between the light-sensing surface is such that the focal point between the lens and the light-sensing surface coincides with each other on the optical axis, so that the working surface is located at the depth of field plane where the effective depth of field intersection point a _a of the two lens optical paths is located, the working surface is at the image sensor The point on the work surface is a when the image clarity on the light-sensing surface is similar. When moving in a direction perpendicular to the optical axis to a, the light reflected by point a passes through lens I, respectively. Images b and b/ having similar sharpness are formed on the light sensing surface S of the image sensor. As can be seen from Fig. 26, ₁₀ is b. The moving distance to W, ^ is the moving distance of bjb, at this time, e. < _ei , 1ο=1ι , that is, after the above adjustment, when the working surface is in the effective depth of field interface, the reflected light of the reflected light on the light-sensing surface of the image sensor is the same or similar through different lens paths. Adjusting the position of the convex lens in the optical axis direction by the above method is the same as the adjustment direction of the first method for solving the problem 2. However, due to different purposes, the amount of displacement may be different, which is required in practical applications. Make the right balance.

4. Problem 4: In the embodiment shown in FIG. 6, the convex lenses of different focal lengths in the three lens paths are arranged concentrically from the inside to the outside in the same optical plane, as shown in FIG. In Fig. 22, since the convex lenses constituting the optical paths of the different lenses are arranged concentrically from the inside to the outside, the convex lens of the inner layer has a small straight diameter and a large effective depth of field with respect to the object distance, but the outer convex lens has a larger diameter. Large, effective depth of field is relatively small relative to its object distance. In order to make the optical path of each lens have a large unique effective depth of field, the optical path of the lens can be improved. The lens is arranged in such a way as to reduce the diameter of the convex lens on the optical path of each lens. 23 and FIG. 24 are top views of the modified lens group in which the lens of each lens optical path is spatially arranged in the cross section of the optical path. In Fig. 23, one of the convex lenses of the five lens optical paths is in the middle of the circle, and the other four are located around the circumference, and are surrounded by an annular shape. In Fig. 24, the four lenses divide a circle into four equal parts, each occupying a quarter circle.

Example 1

7 is an embodiment in which the method 1 of the second problem in the first embodiment and the method of the third problem in the first embodiment are applied, wherein the focusing convex lens is independently imaged by the double lens, and the optical axes of the convex lenses of different focal lengths are separated. The mirror or the reflective prism is used to superimpose the image on the light-sensing surface. By adjusting the position of each convex lens in the optical axis direction, the difference in imaging size and moving speed of each lens can be effectively reduced.

Example 3:

Fig. 8 is another embodiment in which the method of the first problem of the second embodiment and the method of the third problem of the first embodiment are adjusted. The optical axes of the three convex lenses are the same, and the optical paths of the lenses are independent, and the focal lengths are different. The convex lenses of different focal lengths are arranged from top to bottom according to the focal length from long to short. Looking down from the optical axis, looking directly at the lens group, the lenses are arranged concentrically, and the top view of the lens is shown in Fig. 22.

Example 4:

Fig. 9 is another embodiment in which the method of the first problem of the second embodiment and the method of the third of the first embodiment are adjusted. Its three convex lenses have the same optical axis and are superimposed on each other from small to large. The light reflected from the working surface passes through the outer peripheral portion of the lowermost large convex lens, passes through the edges of the upper two convex lenses, and is imaged on the light sensing surface, and the focal length of the lens optical path is the longest. The other part of the light reflected by the working surface is condensed by the area between the middle portion and the outer peripheral portion of the lowermost large convex lens, and then converges through the outer peripheral portion of the intermediate convex lens, and passes over the edge of the upper small convex lens. Imaging on the light-sensing surface, the focal length of this lens path is slightly shorter. The other part of the light reflected by the working surface is concentrated by the central portion of the lowermost large convex lens, and then converges through the central portion of the intermediate convex lens, and passes through the small convex lens at the upper portion to image on the light sensing surface. The focal length of the lens path is the shortest.

Example 5

1Q is another embodiment in which the method 1 of the second problem of the first embodiment and the method of the third problem of the first embodiment are adjusted. The embodiment in the figure uses a single-sided convex lens and three convex lenses of different focal lengths. The optical axes are the same and are layered from top to bottom and arranged concentrically around the optical axis.

Example 6:

Figure 27 is a schematic view of the structure of the embodiment, which is divided into five convex lenses of different focal lengths according to the method of the fourth problem according to the method of the fourth embodiment, and according to the method 1 and the problem 3 in the second problem. A schematic diagram of an embodiment in which the method of adjusting the position of each lens in the optical axis direction is performed. One of the convex lenses of the five lens optical paths is circular in the upper part of the center of the optical axis, and the other four are viewed from the top to the bottom of the convex lens located at the center as shown in FIG. 23, and are surrounded by an annular shape; In the direction of the optical axis, each convex lens is adjusted from short to long from top to bottom in accordance with the length of the focal length. By redistributing the spatial distribution of each convex lens in the cross section of the optical path, the diameter of each convex lens is reduced while maintaining the area of each convex lens in the cross section of the optical path, and the effective depth of field of each lens optical path is increased, thereby increasing the overall Effective depth of field; By adjusting the position of the convex lens on the optical path of each focusing lens in the direction of the optical axis, and moving the working surface within the overall effective depth of field, the difference in imaging speed of the working surface through the optical path of each lens on the photosensitive surface Significantly reduced, and the image quality after image overlap is controlled within the permissible range, forming an image that can be processed and compared by the processing control unit.

In each embodiment, due to the imaging characteristics of the spherical convex lens, the above-described embodiment mainly uses a spherical convex lens as an illustration, but in the multi-lens optical optical imaging device of the present invention, in order to adjust the focal length and imaging quality, etc., in the lens group Concave lenses or various types of prisms and aspherical convex mirrors are also often used, but this does not detract from the spirit of the invention and does not affect the innovative features of the invention.

In addition, due to people's inclined pen holding habits, in order to correct the resulting trapezoidal distortion of the imaging, the lens group is often corrected by various types of mirrors, prisms and other aspherical side mirrors, and will not be described here. .

The multi-lens optical path lens imaging apparatus for a mouse according to the present invention has an effect of providing a much larger effective depth of field than a single-focus imaging lens in a narrow space of a mouse (particularly a pen-shaped mouse), and can secure it The image quality enables the image sensor to correctly capture the moving distance and direction of the image formed by it, so that the mouse can be accurately positioned when the pen is pen or pen, so that the movement state of the mouse on the working surface can be correctly recognized.

The present invention is not limited to the embodiments described above, and it will be understood by those skilled in the art that changes and modifications can be made thereto without departing from the spirit and scope of the invention as defined by the appended claims. .

Claims

Profit request

1. An optical imaging device for an optical mouse, comprising: two or more lens optical paths), the light reflected by the working surface (4) passes through a corresponding different lens optical path (A) in the image sensor (1) The image is formed on the light-sensing surface and superimposed.

2. The optical imaging device of the optical mouse according to claim 1, wherein each of the lens optical paths (A) corresponds to a different unique effective depth of field segment, and the unique effective depth of field of the different lens paths is in the optical axis. The direction of each other continues to form an overall effective depth of field that is significantly longer than the effective depth of field of the single lens path; the above two or more overlapping images have at least one optical path forming a clearer image within the overall effective depth of field. The image formed by the image and other optical paths or blurred or sharp overlaps on the light-sensing surface of the image sensor U).

3. An optical imaging device for an optical mouse according to claim 1, wherein said working surface (4) always has a working surface (4) when moving laterally relative to the optical axis in the overall effective depth of field. The effective depth of field corresponding to the location, the light reflected by the working surface (4) passes through the lens optical path corresponding to the effective depth of field segment) to form a clear image on the light sensing surface of the image sensor (1); After the lens light path is formed independently of each other, each image is superimposed on the light sensing surface of the image sensor (1) to form an overlapping image for the processing control unit (2) to perform contrast processing and positioning.

4. The optical imaging apparatus of an optical mouse according to claim 1, wherein said lens optical path is a focusing lens optical path including a convex lens (3); each lens optical path (A) is one or more a focusing lens optical path composed of a convex lens and/or a concave lens and a mirror; when the light sensing surface is located above the lens group, in the optical axis direction, the focusing lens groups of different focal lengths constituting the optical paths of the respective focusing lenses are made from a long focal length to a short focal length. The location of its placement is adjusted from top to bottom.

5. The optical imaging device of the optical mouse according to claim 1, characterized in that the convex lenses (3) of the respective lens paths have different focal lengths; the optical axes of the respective convex lenses (3) may coincide or separate; The convex lenses (3) are on the same optical plane.

The optical imaging device for a pen-shaped optical mouse device according to any one of claims 1 to 5, characterized in that the lens optical path U) comprises a plurality of lens optical paths composed of a plurality of convex lenses (3). The convex lenses (3) of the optical paths of the respective lenses have different focal lengths, and the optical axes coincide, and several The convex lens (3) is arranged concentrically in the same optical plane from short to long from the inside to the outside, and the effective depth of field corresponding to the lens path of different focal lengths continues on the optical axis from top to bottom to form a long overall effective depth of field. .

The optical imaging apparatus for a pen-shaped optical mouse device according to any one of claims 1 to 5, wherein the lens optical path (A) comprises a plurality of independently imaged double-lens focusing convex lenses (3), different The optical axes of the two independently imaged double-lens focusing convex lenses (3) of the focal length are separated, and the images are superimposed on the light-sensing surface of the image sensor (1) through a mirror or a reflecting prism (5).

The optical imaging apparatus for a pen-shaped optical mouse device according to any one of claims 1 to 5, characterized in that the lens optical path (A) comprises a plurality of lens optical paths composed of a plurality of convex lenses (3), each The optical axes of the convex lenses (3) of the strip lens paths are the same, and the optical paths of the lenses are independent, and the focal lengths are different. The convex lenses of different focal lengths are arranged from top to bottom according to the focal length from the top to the bottom, and the lens group is directly viewed from above the optical axis. It can be seen that the lenses are arranged concentrically.

The optical imaging apparatus for a pen-shaped optical mouse device according to any one of claims 1 to 5, characterized in that the lens optical path (A) comprises a plurality of lens optical paths composed of a plurality of convex lenses (3), each The optical axes of the convex lenses (3) of the strip lens paths are the same, and are superposed on each other from small to large from top to bottom.

The optical imaging apparatus for a pen-shaped optical mouse device according to any one of claims 1 to 5, wherein the lens optical path (A) comprises a single-sided convex lens (3) having a plurality of convex lenses. A plurality of lens optical paths, and a plurality of convex lenses having different focal lengths have the same optical axis, and are layered from top to bottom, and are arranged concentrically around the optical axis.