TW474094B - Light guide device of image scanner - Google Patents

Abstract

A light guide structure used in the contact image sensor device is disclosed, this light guide structure comprises a light source device formed of a LED and light guide, the LED is adhered to the side of the rectangular stripe-like light guide and the incident light from the point light source is incident into the light guide and enters into the whole rectangular stripe-like light guide using total internal reflection principle. The cross section of the rectangular stripe-like light guide is elliptical, the upper and lower long sides is part of the smooth curve from the ellipse, the left and right cross sections form the scattering center and exit face. The crossed position of the scattering center is at one focal point of the ellipse, and the crossed position of the exit face is between the center of the ellipse and the other focal point. Thereby the scattered light from the scattering center can be emitted from the exit face. This design of light guide not only can make the best use of light, but also can save the cost since it is not necessary to proceed the coating treatment on the reflection surface.

Description

474094 A7 B7 V. Description of the invention () Field of the invention: The present invention relates to a light pipe structure, especially an elliptical light pipe structure used in a contact image sensor (CIS) device. Background of the Invention: With the development of technology, all kinds of information products are constantly updated and generated. For image capture devices such as digital cameras or scanners, they are no longer regarded as unpopular or specialized fields. Products, especially for scanners, whether they are paper-feeding, platform-type or various high-end and low-end products can meet users with different needs. '' Acquired image scanning device (Please read the precautions on the back before filling this page}

A member of the Intellectual Property Bureau of the Ministry of Economic Affairs ^ uses an external or handheld scanner. The most commonly used light sensing device is a Charge-Coupled Device (CCD). Generally, in the CCD residual Macao load, light sources, reflectors, and lenses are needed to adjust the light, which has a large volume. In addition, there is a scanner composed of a contact image sensor (CIS). The f, sensor source, lens, and sensing element can be combined in a smaller space to light it more. For convenience and space saving, it has become a 'use flow' in Swipe F 3. The main picture is the traditional CIS sensor. The reference numeral 140 is a case containing the entire CIS sensor element surface structure, and the upper half plane of the case 1 40 is a case where the text to be scanned is placed. Located on this paper standard applicable to China National Standard (CNS) 8 4 specifications (210X297 mm)

4 ^ 4094 A7 B7 V. Description of the invention () The bottom of the case 1 4 0 is the circuit board 1 0 0, which has an important light sensing element 1 1 0. The light sensing element can generally be C μ 0 S or appropriate Consisting of light sensing elements. A lenticular lens array 1220 is additionally disposed above the light sensing element 1 丨 0, and a light pipe type light source device 130 is located beside the lenticular lens group array 丨 2〇. When the CIS is operated, the uniform linear light source 16 emitted by the light pipe type light source device 13 will be incident on the document to be scanned 150 and then transmitted through the lenticular lens array 20 and the light sense. The measuring element 1 丨 〇 receives this image signal and processes it. Shown in the second figure is a conventional light pipe type light source device. In the elongated light pipe 200, a light emitting diode (Led) 220 will be attached to the side of the light guide officer. 'The light emitted by the LED 220 will be incident into the light pipe to generate total reflection.' The appropriate light guide design will The light is guided to a fixed light emitting direction, such as the light emitting surface 210 shown in the figure. However, 'in order to increase the efficiency of the light source of the long light pipe, the traditional light pipe design will form easily scattered light spots in specific places in order to guide the light out through the light exit surface, but the design of this type of light pipe is due to Its shape is not good, it is easy for the light to destroy the condition of total reflection due to irregular reflection, causing the light to leak out of the light pipe. For example, the light pipe 200 shown in the second figure will form a scattering point at the bottom of the light pipe, and the light exits the light pipe 200 through the light exit surface 2 10. Due to the excessive loss of light, this type of traditional light pipe cannot effectively use extremely limited light sources. This paper size applies the Chinese National Standard (CNS) A # specification (21〇χ 297 mm (please read the note on the back first) (Fill in this page again)

, 1T

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs of the People's Republic of China 474,094. V. Description of the invention (A7 B7 Therefore, the traditional light pipe is shaped like 4, β η, and the light source device is not the best. It needs a new umbrella. The light pipe structure is used to improve this disadvantageous factor. Objective and summary of the invention: In view of the above background of the invention, the traditional light guide is not designed to make the light use efficiency poor, so the main purpose of the present invention is δ Another kind of light guide structure of a contact image sensor is used to make it easy to control the total reflection of the light source to generate a better light source usage rate, without the need for additional processing, and easy to produce and design. Using the light pipe structure of the present invention It will be summarized as follows: 1. The light source device, which is composed of a light emitting diode (LED) and a light pipe: f. The light emitting diode is composed of different colors of red, green, and blue, and is attached to the side of the strip light guide. Side, a point light source is incident into the light pipe. In order to improve the use efficiency of the light source device of the present invention, the cross section of the light V official used in the invention is an ellipse as The basic cross section is shaped, and a first plane is cut out at one of the focal points of the oval cross section, and a special ink is made on it to make it a scattering surface of the light source; in addition, at the center point of the oval cross section And another focus, take a suitable position and cut out the first plane, this second plane is, the light exit plane, (or the light exit plane). Due to the elliptical special life, when light passes through one of them When the focus is emitted, it will be focused on another focus after being reflected by the elliptical surface. For this reason, in the light pipe of the present invention, if the light enters from the side of the light pipe and is reflected to the scattering point on the scattering surface, 'The light emitted by the scattering point will pass through the ellipse on both sides. The paper size is applicable to China. A4 ^ m (210X297 ^ 7 _______ 丨' 丨-(Please read the precautions on the back before filling this page), 11

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 4 ^ 4094 A7 B7 V. Description of the invention () Total reflection of the cylinder surface to focus on another "virtual", that is, the light will be emitted from the "plane," (Please read the precautions on the back before filling out this page) In addition, 'peripheral components that cooperate with the light pipe light source device of the present invention' also include, for example, a sensing element, which is an image signal sensing element such as Complementary metal-oxide semiconductors (CM0S), etc., can be arranged in a linear receiving unit to receive the focused image light, and then be processed by subsequent circuits. Cylindrical lens group, when the linear light emitted by the light pipe light source device After being reflected by the document to be scanned, it will be focused through the lenticular lens group so as to be received by the sensing element. In order to receive a linear image signal, the lenticular lens group is also arranged in a long strip array. The design of the light pipe will obtain an optimal illuminance at the light exit plane, and at the same time, the reflection of the elliptical surface exactly meets the total reflection Conditions, so the surface of the entire light pipe, in addition to the scattering points on the scattering surface, does not require additional processing, and can reduce additional manufacturing procedures, so it is a relatively simple and easy to produce design. The diagram simply explains: The preferred embodiment of the present invention printed by the Employees' Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs will be explained in more detail in the following explanatory texts, with the following figures, where: The first figure shows the contacts formed according to traditional methods Schematic diagram of the cross-section of an image sensor; This paper size applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) 474〇A7 B7 i. Description of the invention () The second figure shows a contact image formed according to the traditional method The light guide of the sensor is a schematic diagram; the third diagram is a schematic cross-sectional view of a contact image sensor formed according to a preferred embodiment of the present invention; and the fourth diagram is a preferred embodiment according to the present invention Schematic cross-sectional view of the oval light guide of the formed contact image sensor. Detailed description of the invention: In the application of the contact image sensor (CIS), The design of the light guide is to make the point light source form a uniform linear light source after multiple total reflections in the light guide. Therefore, the bottom surface of the light guide usually has a scattering center. However, The traditional design cannot achieve the optimal effect in the use of light energy. Therefore, the present invention develops a light pipe structure of different contact image sensors according to this problem, and uses the light pipe structure formed by the present invention. The features will be described as follows: First, refer to the third figure, which is a schematic cross-sectional view of a contact image sensor formed in accordance with the present invention. The CIS module is long and can be issued. The linear light source is used to form a horizontal scanning line in the scanner, but its cross section is taken here for convenience of explanation. The CIS module in this figure will be supported and surrounded by a shell structure 140, which can Each component in the CIS module is fixed in the module to avoid poor scanning results due to changes in the relative distance between the components during operation. The paper size is applicable to China. Standard (CNS) A4 size (210X 297 mm) --------4! (Please read the notes on the back of this page and then fill in) order

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 474094 A7 B7

In this CIS module, the light source device consists of a light pipe 〒s i3 0 and a light emitting diode (LED) attached to its side (not shown in this figure). One & three T 丄 which respectively represent different colors of red, green and blue (RGB) are attached, and the light pipe 130 is made of acrylic or other suitable materials. Optically, the principle of total reflection will be used to make, for example, the light emitted by the point light source formed by the LED above enter the light pipe and then be controlled to move along the direction of the light pipe. Basically, the light should be transmitted along the light pipe as much as possible. Avoid ^ = energy loss, so the materials used must be very uniform, and the light absorption rate should be extremely low. The surface of the light pipe must also be very smooth, otherwise the valley will easily cause irregular reflection of light and destroy the condition of total reflection. In the present invention, after the light is incident into the light pipe 30, it undergoes multiple total reflections and scatterings and is emitted from the plane of the light from the '', (or referred to as the light exit surface) 70 as a linear light source. At the same time, in the light pipe device of the present invention, although it is still a long light guide, the cross section is as shown in the third figure, the two long sides are arc-shaped, and the light exit surface 1 7 0 And the scattering surface 1 800 is a straight cross section, and the scattering surface 1 80 is printed with scattering points formed by a special ink. The light guide member 130 thus designed, due to its special shape and a specific scattering point position, as long as most of the light is incident on the scattering point, most of the light will be totally reflected and emitted from the light emitting surface 170. In other words, this light pipe design has the effect of easily reflecting light. As for its formation method, it will be described in detail below. Referring first to the fourth figure, this figure is a schematic cross-sectional view of a light pipe according to the present invention. The cross-sectional shape of the light pipe 13〇 can be clearly seen from the figure. This paper scale Gu towel _ (CNS) '210X297 ^) (Please read the precautions on the back before filling this page)

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs ^^ 4094 A7 B7 V. Description of the Invention () The print of the Employee Cooperative Cooperative of the Intellectual Property Bureau of the Ministry of Economics actually comes from a slender oval shape with two axes of different lengths. At the same time the long axis is also divided into two focal points F i and F2. A cross section will be performed between the center of the elliptical cross section and one of the focal points F1 to cut out the first light emitting surface 170 as shown by the dashed line in the figure. The actual light emitting surface 170 can be located according to the size of the CIS module and the light gathering. , And actual use. In addition, a second scattering surface 180 (as shown by the dotted line in the figure) is cut out at another focal point F2, and at the same time, a rough surface, printing paint, or special ink is printed on the scattering surface 180. This way forms scattered spots of varying sizes. In addition, the light emitting surface 170 and the scattering surface 180 may form two planes parallel to each other. Basically, through such deliberate manufacturing and control, defects, which can meet the needs of some special applications. For example, in CIS, there is a need for a linear light source to generate uniform illuminance on a strip-shaped surface, so a series of, defects, and point arrangements are manufactured on the scattering surface 180 of the strip-shaped light pipe, with proper arrangement. The size and position of these defects can be used to obtain the required linear light source. The elliptical reflecting surface has special light characteristics due to its special shape. When a point light source is placed at any of the focal points', the light emitted by it will be focused on another focal point after being reflected by the ellipse. At the same time, the total length of the optical path will be constant regardless of the point reflected by the expansion. Value. In view of this characteristic of the ellipse, in the elliptical cross-section light pipe of the present invention, since the scattering surface 1 0 0 is cut along one of the focal points ρ 1 and a scattering point is made on it, all are projected onto the scattering surface 丨 8 Most of the light on 〇 can meet the condition of total reflection and is reflected to another focus F2 via an elliptic cylinder, but because the light-emitting surface is broken at the center of the ellipse and the focus F j — — — — i ! (Please read the notes on the back before filling out this page) Order

X 297 mm) 4 ^ 4094

V. Description of the invention (Because of this, all the reflected light will be emitted through the light exit surface 170. Furthermore, because the light use efficiency is increased because of this special light pipe shape, the elliptical reflection surface of the light pipe 130 is not required The special production of the scattering layer or the processing of the reflective surface can save the manufacturing process and is a very simple and easy-to-manufacture design. · Returning to the third figure, in fact, the above-mentioned light pipe 1 should be operated by a scanner. The uniform linear light source emitted by 30 is irradiated onto the document to be scanned 15 after being refracted by 160, and the reflected light passing through is incident on the lenticular lens array 丨 2 〇 to be focused, such as a complementary metal oxide semiconductor ((: ^ 1〇 3) The signal processing steps of the sensor element's receiving performance. To scan the entire document, the transmission mechanism needs to drive the CIS module to perform vertical scanning. Platform scanners are usually equipped with a stepping motor. Wait for the transmission responsibility to push the CIS module forward. The horizontal resolution file U 0 of the general scanner is related, but the vertical resolution can be controlled by the routine When it is changed, the document is covered by a glass cover of 150, and then the back-scanner is used to print the conventional system with negativeness and sensing. In the contact image sensor module, there are many different light pipe designs in consideration of the efficiency and cost of the light source. However, these design departments often cannot effectively use the intensity of the light source to allow the limited light source to leak out of the light pipe. Loss, but in the light guide structure I produced by the elliptical cross-section of the present invention, due to the effective use of the elliptical optical characteristics, light can be finally reflected in the light pipe after being totally reflected in the light pipe multiple times. The scattering point at the jealous focus is successfully re-reflected and scanned by the light-emitting surface 乂 J.

(Please read the notes on the back before filling this page)

474094 A7 B7_ V. Description of the invention () The new scattering mechanism can concentrate the leaked light energy to the target direction, which can further improve the efficiency of the use of light energy. (Please read the precautions on the back before filling this page) As understood by those familiar with this technology, the above is only a preferred embodiment of the present invention, and is not intended to limit the scope of patent application for the present invention; all other Equivalent changes or modifications made without departing from the spirit disclosed by the present invention shall all be included in the scope of patent application described below. The component symbol indicates: 140 The housing structure including the entire CIS sensor element 150 The document to be scanned 100 Circuit board 110 Light sensing element 120 Cylindrical lens array 130 Light pipe type light source device 160 Uniform linear light source 200 Long Light Pipe 220 Light Emitting Diode (LED) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 170, 210 Light emitting surface 180 Scattering surface "This paper is also applicable to China National Standard (CNS) A4 (210 X 297 mm)

Claims (1)

474094 6. Scope of patent application 1. A light source device, the device includes at least: a light guide, the light guide is a long strip, and the shape of its cross section is cut from the elliptical shape into a first plane and a first plane. Composed of two planes, the first plane is a light-emitting surface, and is located between the elliptical midpoint and the first focus; the second plane is a scattering surface, and is located on the elliptical second focus; a light-emitting diode Attached to the side of the light pipe to provide a point light source into the light pipe. ----- 1 .— (Please read the precautions on the back before filling out this page) The description of the tube light guide is its installation source. At the time when the light is broken, there is a first upper surface ΤΠΊτ / one second, please ask the application of the point shot as described above in the installation of the source light item 2 ο the second surface of the structure of the surface is rough Please make a rough claim for item 2 of the source light installation in the above description of point emission. Wei Chenghuan ’s law firm specifically requested that you apply for the application of the light guide by the Ministry of Economic Affairs, the Intellectual Property Bureau of the Ministry of Economic Affairs, the employee ’s consumer cooperative, and the print of the mutual relationship. Wo Fan specifically requested that the layer 1 should be applied as described in the first paragraph of the anti-fan anti-passing law. Would you like to apply Shen Zhouru's tube light guide in the installation of the source light? · »» This paper size Applicable to China National Standard (CNS) A4 (210 X 297 mm) 474094 6. Scope of patent application 7. For the light source device in the scope of patent application item 1, the above-mentioned light-emitting diodes are composed of different colors of red, green, and blue (RGB). 8. The light source device according to item 1 of the patent application scope, wherein a linear light source is formed. 9. The light source device according to item 1 of the scope of patent application, wherein the light emitted by the light-emitting diode is emitted from the first plane of the light pipe. 10 · —A contact image sensor (CIS) device, the device includes at least: a light source device, a light guide with a long strip and a light emitting device 2 attached to the side of the light guide The shape of the cross section of the light pipe is cut from an elliptical shape into a first plane and a second plane. The first plane is a light emitting surface and is located between the center of the ellipse and the first focus. The second plane is a scattering surface and is located on the second focal point of the ellipse. The light source device forms a linear light source. The lenticular lens reflects the linear light source of the light source device through a document to be scanned to form an image signal. Lens lens focusing; A sensing element receives the image signal after the lenticular lens is focused and processes it to form a digital image. 1 1. The contact image sensing device according to item 10 of the patent application scope, wherein the second plane of the light pipe described above has a scattering point. 12 This paper size is in accordance with Chinese National Standard (CNS) A4 (210 X 297 mm) »ninns ammt ii fn nn« n —Ϊ · nnn 111 1 I · nnnnnnd I — (Please read the notes on the back before filling in this Page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 9 ο 4 7 4 A8B8C8D8 9 (1 VI. Patent application scope 12 · If the patent application scope item 10 is a contact image sensing device, the above-mentioned scattering surface is It is composed of rough surface. 1 3 · As in the contact image sensing device of the scope of patent application No. 10, wherein the first plane and the second plane of the light pipe are parallel to each other. 1 4 · If a patent is applied The contact image sensing device of the scope item i 0, wherein the surrounding of the above light pipe is not processed by the reflective layer. I 5 · The contact image sensing device of the scope of the patent application item 10, wherein the above The light-emitting diode is composed of different colors of red, green, and blue (RGB). 16. The contact-type image sensing device according to item 10 of the patent application, wherein the above-mentioned lenticular lens is formed in a long shape Line in order to receive the linear image signal. 1 7. The contact image sensing device according to item 10 of the patent application scope, wherein the above-mentioned sensing element is a complementary metal oxide semiconductor (CMOS) element (Please read the notes on the back before filling this page) ni US · i:-一-«4I d ϋ n · 1« ϋ i— · Printed by the Employees' Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper is sized to the Chinese National Standard (CNS) A4 (210 X 297 mm)