DE20203019U1 - Module to extend the total beam path - Google Patents

Description

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Module for extending the total beam path

The present invention relates to a module for extending the entire beam path, in particular in an optical detection device.

Some optical imaging devices, such as scanners, copiers, high-resolution fax machines, cameras, and video cameras, use a basic scanning principle in which light from a light source strikes an object to be scanned, reflected or transmitted light from the object to be scanned passes through a lens, and is focused in an imaging device such as a CCD (charge couple device).

Typically, these optical image capture devices require a beam path device to reflect or refract the light from the object to be scanned. Consequently, the light paths have a suitable length (or also called light beam paths) to be focused and as a result produce a sharp image in the imaging device.

Referring to Figure 9, a known optical reflection device of a scanner housing is shown. A document page 1 of an object to be scanned is fed to a platen glass 2, a lower light 3 directs a light beam la upwards and an image light beam Ib is then directed to a mirror 4, an image light beam Ic is reflected by a mirror 5, whereby a plurality of light beams Id, Ie and If are reflected between the mirror 5 and a mirror 6. A light beam Ig penetrates a lens 7 and then a

Light beam lh is emitted and forms an image in an image sensor 8 (CCD, Charge Couple Device). A scanner housing 9 has a certain internal space, so that two methods for extending the total beam paths are possible, one method consisting in repeatedly changing the dimensions of the scanner housing 9 in order to extend the total beam path. However, this method is not within the scope of the present invention, since this is precisely what is to be avoided. The other method provides that the number of reflections is increased in order to achieve the result of extending the total beam path. Figure 9 shows such a device for increasing the reflection possibilities, wherein the mirrors 5 and 6 are enlarged in order to enable an increase in the number of reflections, but the costs are higher than before due to the increased dimensions of the mirrors.

According to Figure 10, another known optical reflection device of a scanner housing is shown. A document page 1 of an object to be scanned is provided on the support window 2, wherein a lower light source 3 directs a light beam 2a upwards and then an image light beam 2b is generated at a mirror 4, wherein an image light beam 2c is reflected at a mirror 5, and wherein a light beam 2d is reflected at a mirror 6 and a light beam 2e is reflected at a mirror 10. A light beam 2f penetrates a lens 7 and then a light beam 2g is emitted and an image is generated in an image sensor 8. Figure 10 thus shows a further embodiment for increasing the number of light reflections, in which the number of reflection elements used is increased, which also increases the costs due to the increase in the number of reflection elements.

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The known optical reflection device comprises several mirrors (3 or 4 are common) and relevant positions and angles between the mirrors, which are taken into account when they are assembled. If a position or angle of a mirror is not precisely aligned, the following light rays and the distances between the mirrors are affected. In particular, if the position or angle of the mirror 4 (the 1st mirror for the reflected light) is not precisely aligned or the function or positioning of the device is not perfect, the image quality can be greatly deteriorated due to tolerance deviations.

For an optical reflection device for large scanning dimensions, the total beam path is relatively lengthened. Usually, in most known methods to achieve the total beam path, the distance between the mirrors is increased and the number of reflections of the light is increased. However, to increase the distances, an optical reflection device is also increased and thus it is no longer economical; thus, this method cannot follow the general trend of providing smaller electronic products. To add reflections, the number of mirrors increases and thus the weight of the optical reflection device. Furthermore, the many mirrors and the position adjustments increase the costs. Another point is that the effect of tolerance deviations increases proportionally with the number of mirrors. In addition, more light is refracted in and outside the mirrors, which causes increased scattering and light decay phenomena, which negatively affect the scanning quality.

Figure 11 shows the third embodiment of a known optical reflection device from a scanner housing

The figure shows a prism which allows an increase in the number of reflections in a limited space. A light source 11 provides a downward-directed light beam to penetrate a support glass 2 and then to a first reflection mirror 12 of the prism. The light beam continues to a second reflection mirror 13 and leaves the prism. A decisive disadvantage of this design is that each prism is only suitable for a single reflection path and therefore a light reflection path (comprising reflections and total light beam path inside the prism) is not flexible and cannot be adjusted with regard to the reflection mirrors and their positions. For different objects to be scanned with different total beam paths, different scanner dimensions or different solutions result, whereby the prism must always be redesigned in order to take into account the different conditions, such as those mentioned above. Furthermore, these parts may not be common and cannot be accommodated in a module, increasing the costs of design, manufacture and packaging.

Based on the above-mentioned results, the present invention is based on the object of proposing a module of the type mentioned at the outset, in which the above-mentioned disadvantages known from the prior art are avoided.

Accordingly, a module according to the invention for extending the entire beam path, in particular for an optical detection device, is proposed, which can change the overall beam path without the reflection positions and reflection space of the optical detection device having to be moved outside. It

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It is possible to use several different modules to enable different overall beam paths through the present invention. Furthermore, the modules according to the invention can be easily and quickly replaced in an optical detection device.

It is a further object of the present invention to propose a module for extending the total beam path for use in different beam paths with different modules in a limited space. The modules according to the present invention can be easily replaced by any other module for increasing efficiency, these modules being available for different total beam paths, thereby eliminating the need to provide a new total beam path system for different conditions, thus keeping costs low. In addition, by adjusting the positions of the light sources in an optical detection device, modulation of the reflection frequency and the total beam path can be made possible, so that the use of new or multiple optical detection devices is no longer necessary. In this way, modulated parts are saved, the development costs for the parts are reduced, and storage costs are also reduced.

Another object of the present invention is to propose a module for extending the total beam path, which allows a significant reduction in the number of reflection mirrors for the same total beam paths, to reduce the assembly costs, to eliminate the tolerance deviation of reflection angles and to reduce the total reflection volume.

Another object of the present invention is _to propose a module for extending the total beam path which enables various total beam paths and offers solutions without changing the original document position and the image scanning position. The module can use multiple reflections to extend the total beam path, thereby achieving the above object.

The accompanying drawings show further illustrations of the present invention and the following description illustrates the principles of the invention.

Show it:

Figure 1 a first representation of the technical principle

of the present invention;

Figure 2 a second representation of the technical

Principle of the present invention;

Figure 3 shows a preferred embodiment of a

Single mirror module according to the present invention;

Figure 4 is a three-dimensional representation of a

Single mirror module according to the present invention;

Figure 5 shows a preferred embodiment of a

Three-mirror module according to the present invention;

Figure 6 is a three-dimensional representation of a

Three-mirror module according to the present

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Invention;

Figure 7 shows a preferred embodiment of a

Four-mirror module according to the present invention;

Figure 8 shows a preferred embodiment of a

Round mirror module according to the present invention;

Figure 9 a known optical reflection device

a scanner housing;

Figure 10 another known optical

Reflection device of a scanner housing; and

Figure 11 shows a third known optical

Reflection device of a scanner housing.

The present invention comprises an optical detection device which has a light source, a lens, a plurality of reflection mirrors and an image sensor (CCD). The light source generates a light for a module for increasing the total beam path with at least one reflection. The lens focuses and reshapes this light in an image generating device. The module is provided so as to be attachable and replaceable to the image generating device, whereby the change of different modules is possible which are required for different total beam paths. The modules have at least one reflection mirror or several reflection mirrors for one or more reflections for different total beam paths.

A main idea of the present invention is to equate an angle of incidence of the light with an angle of reflection of the light, whereby a light beam path of an incident light coincides with a light beam path of an outgoing light at a point which is usually on a normal of the angle of incidence and the angle of reflection. For example, in the case of a single reflection, an incident light creates a reflection point on a reflection element, whereby this reflection point coincides with the incident light path (light incidence path) and the outgoing light beam path (light outgoing path) in the case of double or multiple reflections. According to Figure 1, a first representation of the technical theory of the present invention is shown. A dashed line A represents an imaginary mirror to show the aforementioned single reflection. An incident light path 100 and a normal to A form an angle of incidence α, the light incident path 100 hits a point Xl on the imaginary mirror A and then forms a reflected light exit path 104 with an angle of exit β. The point Xl is then defined by the common point. A double reflection will be described below; if the imaginary mirror A does not exist, a light incident path 101 is formed after the light incident path 100 passes the common point Xl. The light incident path 101 then hits a reflection point X2 of a reflection mirror B. Thereafter, a reflection path 102 hits a reflection point X3 of a reflection mirror C, and further, a reflection path 103 passes through the common point Xl to form a path 104 for the light to emerge. Here, a normal γ, an angle of incidence α and a reflection path 103 are defined. and an angle of reflection β is completely the same as in a single reflection. Based on the idea that conditions

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can be changed to extend the total beam path.

According to Figure 2, a second representation of the technical principle of the present invention is shown. The reflection mirrors B and C in Figure 1 are arranged separately in an optical detection device, the present invention accommodating reflection elements in an arrangement which enables a combination of all reflection elements in one body, such as a module for quick replacement. The following shows how the dimensions of the reflection elements for accommodating all reflection elements in an arrangement are determined. In Figure 2, a triple reflection is provided, wherein several predetermined conditions, such as the direction of a light incidence path 100, the direction of a light outage path 104, the common point X1 and the length of the total beam path, are assumed. Assuming AL is a symbol representing an extension of the entire ray path, the total length of the light ray path 105 (the ray X1X2), the light ray path 106 (the ray X2X3), the light ray path 107 (the ray X3X4) and the light ray path 108 (the ray X4X1) is identical to ΔL. Here, a plurality of points X2, X3 and X4 are individual reflection points of a plurality of mirrors D, E and F. The light ray paths are defined by the direction of the light incident path 100 and if the angle of incidence is equal to the angle of reflection, the light paths 105, 106, 107 and 108 can be derived step by step through the predetermined total ray path AL, the direction of the light exit path 104 and the common point Xl. Therefore, the dimensions of the reflection mirrors D, E and F are fixed and the module for extending the total beam path can thereby be provided.

Figure 3 shows a preferred embodiment of a single mirror module according to the present invention. Prerequisites for the embodiment are not increased dimensions of the mirrors and the scanner housing, consequently a single mirror module 20 is added, whereby the total beam path is immediately increased, as shown in the figure. The single mirror module 20 is independent of the scanner housing 9. The single mirror module 20 is designed in such a way that the single mirror module 20 can be easily replaced by another module. Figure shows a three-dimensional representation of a single mirror module according to the present invention. The single mirror module 20 is cubic, which can be provided on the scanner housing by a fastening device and can be fastened and exchanged, thus different modules can be provided on the scanner housing 9 for different total beam paths. The fastening device has a pin element 201, which can be inserted into a pin recess 209 of a single mirror module 20. The pin element 201 of the fastening device can be extended into the scanner housing 9 for fastening. The fastening device 201 can be designed identically on both sides of the single mirror module 20. The single mirror module 20 is axially divided into two parts, namely a light inlet 205 and a light outlet 207, thus incident light enters the single mirror module 20 via the light inlet 205 and strikes the inclined mirror 203, wherein the inclined mirror 203 creates a reflected light path which penetrates the light outlet 207 so that the light can exit. The above description is based on Figures 3 and 4. The mirror 203 is a thin strip and is fixed to the single mirror module 20 by an inclined insert.

The dimensions of the two longer sides of the mirror 203 are approximately identical to the dimensions of the two longer sides of the single mirror module 20 in order to fix the mirror 203 in the cubic body of the mirror module 20. An oblique angle for the mirror 203 is suitable in order to set the angle of incidence approximately equal to the angle of reflection. For details, reference is made to Figure 1.

Figure 5 shows a preferred embodiment of a triple mirror module according to the present invention. The embodiment is an extended embodiment of Figure 3. Obviously, in this embodiment, a triple mirror module is provided in which twice as much is reflected as in the embodiment according to Figure 3. Therefore, the total beam path is longer. A three-mirror module 30 according to this embodiment is also independently interchangeable. The theory of the light beam paths of this embodiment is the same as in Figures 1 and 2 and is therefore not described further. Figure 6 shows a three-dimensional representation of a three-mirror module according to the present invention. The fastening device in Figure 6 is designed like the fastening device in Figure 4. Light penetrates the three-mirror module 30 through a light inlet 309. It then hits a first reflection mirror 303, then a second reflection mirror 305 and then a third reflection mirror 307. The light then exits the module 303 through a light outlet 311.

Figure 7 shows a preferred embodiment of a four-mirror module according to the present invention. As already mentioned, the multiple reflection also lengthens the total beam path. Accordingly, the idea of the present invention is to achieve the best possible extension of the total beam path even under different

conditions and also a quick change of different modules.

According to Figure 8, a preferred embodiment of a round mirror module according to the present invention is shown. The embodiment is made possible by a round reflection surface which does not differ from the reflection mirrors in terms of a critical number, since a round reflection surface is able to reflect any angle. In Figure 7 it is shown that if one angle of a reflection mirror is faulty, then the entire reflection is also faulty. Therefore, this embodiment provides a complete module with a round inner surface to avoid the aforementioned problems.

While the present invention has been shown and described with reference to the preferred embodiment and illustrated in the drawings, the invention is not limited thereby. For example, all of the above embodiments have mirrors made of reflective material, but other methods of obtaining reflective elements are also possible, such as plating, vapor deposition, electroplating or the like. The base material for the coating can be, for example, glass, plastic, metal or the like. All of the above embodiments provide scanners as the optical detection device, but several other products or devices can also be used instead of scanners, such as copy machines, high-resolution fax machines, digital cameras, video cameras or the like. Furthermore, not only one module can be used in optical detection devices, but several modules are also possible. Accordingly, the present invention is unlimited in terms of its application. In addition, various

Modifications may be made by one skilled in the art to vary the design and content of each embodiment without departing from the scope and spirit of the present invention.

In summary, the present invention proposes a module for extending the total beam path, particularly for use in an optical detection device. Each module according to the invention for extending the total beam path can be replaced without moving the total beam path and the reflection positions outside the optical detection device. Several different modules can be provided in order to enable different total beam paths in the detection device with the present invention. Furthermore, the modules can be easily and quickly replaced in the optical detection device. The present invention is based on a theory in which the angle of incidence is equal to an angle of reflection, whereby a common point is determined by the light incidence path and the light emission path. The aforementioned phenomenon is not only suitable for single reflections, but also for multiple reflections. One reflection element or several reflection elements can be provided in the module according to the invention.

Claims (11)

1. Module for extending the total beam path, in particular for use in an optical detection device, comprising:
at least one cubic structure having a fastening device for fastening and exchanging the cubic structure to the optical detection device to enable different total beam paths, the cubic structure being axially divided into two parts, namely a light inlet ( 205 ) and a light outlet ( 207 ), whereby light can radiate into the cubic structure and out of the cubic structure; and
at least one reflection element which is a thin disk and is provided in the cubic structure, wherein the reflection element is arranged at a suitable oblique angle in the cubic structure, wherein the reflection element has at least two sides with the same length as the two corresponding sides of the cubic structure and wherein the oblique angle is selected such that an angle of incidence (α) and an angle of reflection (β) of the light are equal. 2. Module according to claim 1, characterized in that the reflection element has a plating and/or a vapor coating as the base material for the coating. 3. Module according to claim 1 or 2, characterized in that with identical angle of incidence (α) and angle of reflection (β) and with at least one double reflection, a light incidence path ( 100 , 101 , 105 ) coincides with a light output path ( 104 ) at a point (X1) on a perpendicular (γ) with respect to the angle of incidence (α) and the output angle ( 13 ), wherein for a single reflection the light incidence path ( 100 ) strikes the reflection element at a reflection point (X1), which is the point at which the light incidence path ( 100 ) and the light output path ( 104 ) coincide. 4. Module for extending the total beam path when using an optical detection device, in particular according to claim 1, characterized in that the optical detection device has a light source ( 3 ), a lens ( 7 ), several reflection elements and an image generation device ( 8 ), wherein the light source ( 3 ) emits light which is reflected at least once and is then focused by the lens ( 7 ) in the module ( 20 , 30 ) and processed in the image generation device ( 8 ). 5. Module according to claim 4, characterized in that a reflection element is provided in a cubic structure of the module ( 20 , 30 ), which, with a reflection material on a surface of the reflection element, provides a light incidence path ( 100 , 101 , 105 ) with at least one reflection and a light failure path ( 104 ) after the aforementioned reflection, so that the light can leave the module ( 20 , 30 ), the light failure path ( 104 ) of the light then leading to the lens ( 7 ), the cubic structure being provided so as to be attachable and replaceable to the optical detection device by means of a fastening device, so that different total beam paths are possible through different modules ( 20 , 30 ), and the cubic structure being divided axially into two parts, namely a light inlet ( 205 ) and a light outlet ( 207 ) for the incidence and emission of light, is axially divided. 6. Module according to claim 4 or 5, characterized in that the reflection element has a plating and/or a vapor coating as the base material for the coating. 7. Module according to one of claims 4 to 6, characterized in that with identical angle of incidence (α) and angle of reflection (β) and with at least one double reflection, a light incidence path ( 100 , 101 , 105 ) coincides with a light output path ( 104 ) at a point (X1) on a perpendicular (γ) with respect to the angle of incidence (α) and the output angle (β), wherein for a single reflection the light incidence path ( 100 ) strikes the reflection element at a reflection point, which is the point at which the light incidence path ( 100 ) and the light output path ( 104 ) coincide. 8. Module for extending the total beam path in an optical detection device, in particular according to claim 1 or 4, characterized in that the optical detection device has a light source ( 3 ), a lens ( 7 ), several reflection elements and an image generation device ( 8 ), wherein the light source ( 3 ) emits light which is reflected at least once and then focused by the lens ( 7 ) in the module ( 20 , 30 ) and processed in the image generation device ( 8 ), and wherein the module ( 20 , 30 ) is exchangeably attached to the optical detection device in order to enable different total beam paths with different modules ( 20 , 30 ). 9. Module according to claim 8, characterized in that the module ( 20 , 30 ) has at least one reflection mirror for a single reflection. 10. Module according to claim 8, characterized in that the module ( 30 ) has several reflection mirrors for different total beam paths. 11. Module according to claim 8, characterized in that the module has a circular reflection mirror.