DE102008059903A1 - Document checking device, particularly as verification device for security- or value documents, has detecting unit with multiple detection elements which are arranged in two-dimensional sensing array - Google Patents

Abstract

The document checking device (1) has a detecting unit with multiple detection elements which are arranged in a two-dimensional sensing array. The expansion of the sensing array corresponds to the expansion of the document (9) provided for the detection and defines a detection surface (10) on the support plate (3). An illumination unit (11) comprises multiple illumination elements which are arranged in a two-dimensional illumination array to illuminate an illumination surface (12) on the support plate.

Description

The The invention relates to a document inspection device, with documents can be recorded. Such a document checking device comprises a transparent support plate, a lighting device for Illuminating a arranged in contact with the platen document, a Detection device for the visual detection of the means of illumination illuminated document, wherein the detection means a plurality comprises of detection elements.

With the help of the plurality of detection elements, individual pixels of the document resting on the support plate are detected. In order to ensure a compact, space-saving construction of such document checking devices, so-called contact image sensors, which are referred to in English as Contact Image Sensors (CIS), used. From the EP 0 246 481 A1 For example, a contact image sensor array is known which comprises a series of photoelectric sensor cells, also referred to as sensing elements, each of which is grouped equidistantly along a straight line on a sensor line segment, with a number of sensor line segments forming the contact image sensor array and each sensor line segment comprises a monocrystalline silicon substrate on which the image sensor cells and a drive and signal conditioning circuit for these are formed as an integrated circuit. With a contact image sensor row described therein, only one strip of a document can be recorded at a time in each case. For a colored detection, the individual detection elements can be provided with a color filter, so that the respective detection element detects only one base color of a color system. From the EP 0 246 481 An embodiment is also known which has a plurality of parallel rows of image sensor cells or detection elements in order to accelerate reading in a black-and-white readout or to achieve a doubling of the number of pixels and thus of an image resolution compared to reading with a row in a colored readout of the document. For a compact design to be realized, an imaging optics is completely or at least largely dispensed with. In order to fully capture a document, it is necessary to move the contact image sensor line relative to the document. Here, the document is recorded line by line. It is thus required that the contact image sensor line is moved along an entire extension direction of the document relative thereto.

From the US 5,187,596 a contact image sensor is known, the support plate is formed as an optical fiber array glass plate, wherein the individual fibers serve as imaging focusing lenses. In the described sensor, a lighting element is arranged on a side remote from the support plate side of a photoelectric detection element having a through opening through which the light of the illumination element can pass to illuminate the resting on the support plate document through the support plate therethrough.

From the US 5,650,864 For example, a contact image sensor for color-detecting a document is described, which comprises a plurality of illumination elements that can generate light of different colors or wavelengths. The different lighting elements are driven in a time-shifted manner in order to record different color separations of the recorded document one after the other with the same detection element. These can then be assembled into a color image.

With an increase in mobility within society and an increased need for security has the number the verification of documents, in particular of Security documents, such as passports, identity cards, driving licenses, but also of value documents, such as banknotes, checks, etc., strong increased. This development is accompanied by a need, if possible low-cost, small and energy-efficient document verification systems, particularly as verification devices for security and / or value documents.

Of the Invention is therefore based on the technical problem, an improved To provide a document verification device that meets the above Needs satisfied individually or in combination.

To solve the technical problem, it is intended to provide a document inspection apparatus comprising a transparent platen, a lighting device for illuminating a document in contact with the platen through the platen and a detector for image-capturing the document illuminated by the illuminator Detection device comprises a plurality of detection elements. It is provided here that the detection elements are arranged in a two-dimensional detection array, preferably regularly, wherein an extent of a detection surface detectable by the detection array on the support plate corresponds to at least one extension of the document intended for detection. The extent of the detection area usually corresponds to the extent of the detection array, since no imaging optics is used. The illumination device further comprises a multiplicity of illumination elements, which are arranged in a two-dimensional illumination array, preferably regularly, in order to be able to illuminate an illumination surface on the support plate, the illumination surface covering the detection surface. By forming the detection means such that their detection elements are arranged in a two-dimensional array which defines a detection area provided for fully detecting a document, an acceleration of the document detection is brought about. The detection surface is formed so that it has a surface extension that at least one document ID-1 document according to the standard ISO / IEC 7810: 2003 I can be detected over the entire area. Other embodiments may also fully capture ID-2 or ID-3 documents in accordance with this standard. This is possible because illumination of the document is performed by a lighting device having a plurality of lighting elements arranged in a lighting array. The illumination array is configured so that the illumination elements on the platen illuminate an illumination surface that encompasses the detection surface on the platen. This ensures that a document which rests on the support plate in the region of the detection surface is completely illuminated or can be illuminated by the illumination elements. Such a document checking apparatus does not require any mechanical parts that move the detecting means or parts thereof relative to the document on the platen to completely grasp the document. The energy needed to move the detector relative to the document can be saved. Further, a size of the document inspection apparatus can be reduced because a drive unit and the mechanical components coupled thereto are no longer needed for moving a detection device. Thus, a compact document inspection device is obtained.

A particularly small design can be with one embodiment realize in which several of the lighting elements and several the detection elements on a common semiconductor substrate are formed. This also makes a manufacturing process the document checking device simplified.

Prefers the document checking device has a design of a so-called "personal digital assistant" (PDA) or a so-called "handheld", a portable, in particular one portable in one hand, with its own power supply provided device on.

Even though Nowadays semiconductor wafers with large diameters, for example of 300 mm, it may be advantageous to the detection device composed of several acquisition units. A tolerance compared to manufacturing errors is thereby increased there is a manufacturing defect on a wafer, resulting in multiple acquisition units subdivided, only to one failure and the board of a registration unit and not the entire wafer. At a special preferred embodiment of the invention is provided in that the detection device has a plurality of detection units each comprises a plurality of detection elements and the illumination device several lighting units each having a plurality of lighting elements includes and each a lighting unit and a detection unit are formed on a common semiconductor substrate. This means that both the detection device and the lighting device each comprises several structural units. These structural units represent both a lighting unit and a detection unit, which in turn several detection elements and multiple lighting elements include.

The Manufacturing the detection units of the detection device can for example, in CMOS or CCD technology be. In CMOS technology, it is possible to capture a different Wavelengths in different superimposed to realize arranged levels. As a result, more or less more wavelength-selective or color-selective detection elements on top of each other educated. This means individual levels are for a certain wavelength range sensitive. The capture can be done at the same time, so that a detection time opposite Systems can be shortened in which the graphical Data for different wavelengths or wavelength ranges be recorded one after the other.

Around Evaluate different properties of the captured document To be able to, it is advantageous if the document is through different light can be lit, d. H. through light with different properties. It is advantageous if the Lighting device different types of lighting elements includes, wherein the different types of lighting elements in terms of a property of the light you generate differ.

The Properties of the generated light include a wavelength, a polarization type, a polarization direction and / or a Emission direction. The listed properties are merely to be understood as an example.

For example, a colored capture of the document with non-color selective detection elements, the different types of lighting elements should produce different primary colors of a color system.

at A preferred embodiment comprises the illumination device at least three different types of lighting elements, the Generate light in primary colors of an additive color system. hereby the opportunity is created to color the document respectively with using the same detection elements by three Separations of color of the document are recorded, the Document respectively the light of one of the different types of Lighting elements is illuminated to a color separation of the document with the detection elements to capture. Time after time can recorded as different color separations of a color system and then to a colored image of the document be summarized.

Around a uniform illumination for the light To achieve the different lighting elements, is at an embodiment provided that the lighting elements each of the different types of lighting elements in a, preferably regular, sub-array are arranged, wherein the lighting elements of each sub-array illuminate the detection surface with light of a property can.

Around possible manufacturing differences of the individual lighting elements To be able to compensate, it is advantageous to use the lighting elements To connect a control unit, which is formed, the individual Individually to control lighting elements.

A Such embodiment may also be used to over the individually controlled lighting elements a graphical To generate indication by the platen, which transparent is configured, is visible, if arranged on this no document is. Preferably, therefore, the control unit is formed by means of the individually controlled lighting elements a graphic To realize display.

Around perform a verification of captured documents can, is the detection device in one embodiment coupled to an evaluation unit, which is formed, the evaluate graphical data of the captured document, in particular to verify the authenticity of the document. In particular for such an evaluation, which is a verification it makes sense to provide types of lighting elements, For example, they are able to emit light in the infrared or in the Ultraviolet wavelength range to produce. hereby can have special security features in documents be used, targeted and verified. As well it is advantageous if, for example, types of lighting elements are provided, the light only at a certain emission angle emit the support surface or the document. hereby can provide illumination direction dependent security features be evaluated.

Around to carry out the evaluation, the evaluation unit is preferably trained, from the graphical data of the captured document information to extract and a review of the extracted Information against reference information stored in a database make.

at an embodiment is by means of the graphic display a result of the evaluation graphically displayed. Here you can alphanumeric characters or pictograms are used. As well is it possible for a human viewer unreadable information stored in the document and extracted by the evaluation unit, in a for human information perceivable graphical information, for example using alphanumeric characters, to display and / or output. It has proved to be particularly advantageous, the sub-arrays the lighting elements of the at least three different types, produce the light in primary colors of an additive color system, so to provide that these each have a matrix-like configuration, in which the individual lighting elements in rows and columns are arranged, wherein the row spacings and column spacings the sub-arrays are the same. This means the sub-arrays each have the same row spacing and respectively the same column distances. A row spacing and however, a column spacing of a sub-array need not be equal.

Preferably The detection elements are also matrix-like in rows and columns arranged.

The Row and column distances of the detection elements must not necessarily with the row and column spacing the lighting elements are identical. Particularly preferred however, an embodiment in which the row spacings between the rows of the acquisition array are constant and the Row spacings of the rows of the at least three sub-arrays are the same. equivalent applies to the corresponding column distances.

Particularly preferred are embodiments in which the lighting elements are formed as LEDs. These can be in a Ferti tion process can be formed on the same semiconductor wafer as the detection elements.

at other embodiments are the lighting elements as cells of a LED, OLED, TFT, LCD or plasma screen educated.

at In one embodiment, the detection elements are preferably formed on one or more substrates which are transparent are or have through holes through which the light The lighting elements that come on the from the support surface are arranged opposite side of the substrate or the substrates, on whose side facing the support surface, the detection elements are formed.

at According to one embodiment, the detection elements be designed polarization dependent. This means, that the detection elements only light of a certain polarization direction to capture. Is the light from the lighting elements with a Polarization generated, which is orthogonal to the polarization direction is that can detect the detection element, it is directly from the lighting element does not generate light from the detection element demonstrated. Only the scattered on the document and this in its polarization direction changed light is from Detected the detection element.

Around To obtain a compact design, it is particularly advantageous Circuits for processing the detected signals and / or for Control the lighting elements on the substrate form, on the detection elements and / or the lighting elements are formed are. In one embodiment, on a semiconductor substrate are regular arranged cells formed, each having a detection element and one or more different types of lighting elements as well corresponding circuits for control and signal conditioning include. The individual cells are identically formed and represent one pixel each, both when capturing and when viewing a graphical representation.

Around the detection device, for example, as a verification device being able to operate, it is advantageous the platen with a touch sensing device provided. In such a case, the platen forms a touch panel, which by using a graphical representation that with Help the lighting elements is realized, used as a touch screen can be. This can be a human-machine interface will be realized.

following the invention is based on preferred embodiments explained in more detail with reference to a drawing. Hereby show:

1 a schematic representation of a document inspection device;

2 a schematic plan view of a document inspection device;

3 a schematic sectional view through a differently formed cell; and

4 a schematic sectional view through a cell of a document inspection device.

In 1 schematically is a document verification device designed as a verification device 1 shown. The document checking device 1 includes a housing 2 , In a top of the case 2 is a transparent platen 3 arranged. This is on a top 4 with a touch-sensitive position detection device 5 Mistake.

Below the transparent platen 3 is a detection device 6 arranged, which comprises a plurality of photosensitive detection elements (not shown), which are arranged in a two-dimensional array, which is two-dimensional on one of the support plate 4 facing side 7 extends. This means that the array on the one hand in a direction parallel to one by a double arrow 8th indicated direction and the other in a second dimension extending perpendicular to the plane of the drawing.

The detection device 6 is trained to document 9 which is within a detection area 10 is arranged to capture the entire surface.

The document checking device 1 further comprises a lighting device 11 comprising lighting elements (not shown) arranged in a two-dimensional array. The two-dimensional array extends along a first dimension parallel to the direction indicated by the double-headed arrow 8th is indicated, and in a second dimension perpendicular to the plane of the drawing. The lighting device 11 is designed to be a lighting surface 12 to illuminate. The lighting area 12 includes the detection area 10 , In some embodiments, the sensing surface is 10 and the lighting area 12 congruent.

The detection device 6 is with an evaluation unit 13 coupled, which is formed, by means of the detection device 6 captured image signals a graphical evaluation of the document 9 make. In this case, for example, information can be extracted from the recorded graphical representation of the document and compared with reference information stored in a memory 14 are stored. By way of example, a verification can be carried out as to whether the detected document 9 Has security features that identify this as an authentic document. The evaluation unit 13 can perform a variety of different scans of the captured graphical image of the document.

The lighting device 11 is further provided with a control unit 15 coupled. The control unit 15 and the lighting device 11 are designed so that the individual lighting elements (not shown) can be controlled individually. Preferably, not only an on / off control, but also a brightness control of the individual lighting elements is possible. Since these are arranged in a two-dimensional array, the lighting elements can also be used to form a graphic display. Thus, for example, a result of the evaluation and / or verification of the document can be displayed graphically and by a user through the transparent platen 3 through the document 9 is removed from this. It is noted at this point that the touch-sensitive position detection device 5 Of course, also transparent and is considered as part of the support plate. A combination of a display device with a touch-sensitive position detection device is also known in the art as a touch screen.

Out The prior art are different embodiments for Touch-sensitive position detecting device known. In one embodiment, for example, strip-shaped formed, parallel to each other in planes arranged electrodes arranged in two planes separated by an insulating layer. The electrodes of the different planes are mutually orthogonal oriented. About an evaluation of a capacitive coupling the different strip-shaped electrodes of different Layers, a touch position can be determined. Also other principles of action can be used.

Become represented by lighting device operating options, so can a corresponding "touch" of the illustrated Operating options an interactive operation of the document capture device be made.

In the illustrated embodiment is an interface 16 provided, for example, captured graphical information of the document 9 to transfer to another device. The interface can be designed, for example, as a radio interface, Bluetooth interface or as a wired interface. Any other interface known to those skilled in the art may also be used. In addition, the interface makes it possible to store reference information in the memory 14 the document checking device 1 to save, for example, for a verification of a particular document 9 needed.

The evaluation unit 13 and the control unit 15 are in a preferred embodiment in a microprocessor 17 designed, programmatically the functionality of the evaluation 13 and the control unit 15 at least partially. Parts of the evaluation unit and the control unit 15 can in the detection device 6 and the lighting device 11 be integrated.

It will be apparent to those skilled in the art that in the schematic illustration, the dimensions of the individual elements relative to each other do not correspond to a real embodiment of a document inspection device. Preferably, the document checking device 1 designed as a portable device and has an energy storage 18 on which the individual elements of the document checking device 1 powered. In the energy storage 18 it can be mono cells, an accumulator or the like. A supply via so-called solar cells, ie via photovoltaic, is also possible.

In a preferred embodiment, the detection device 6 and the lighting device 11 formed on one and the same semiconductor substrate. Particularly preferred is an embodiment in which all detection elements and lighting elements are formed on a single semiconductor substrate. Other embodiments provide that the illumination device and the detection device are respectively subdivided or composed of units, ie detection units and illumination units. In this case, a lighting unit and a detection unit may each again be formed integrally on a semiconductor substrate. The lighting elements are preferably formed in such an embodiment as light-emitting diodes.

Preferably, the illumination device has different types of illumination elements that emit light of different properties. The different types of lighting elements are arranged in two-dimensional subarrays. The lighting elements of a sub-array are designed to that they cover the entire lighting area 12 each can illuminate. In one embodiment, the lighting elements comprise at least three types each producing light of three primary colors of an additive color system.

Around also be able to record security features in documents, which are visible only when illuminated with light, which is not in the visible wavelength range are in some Embodiments provided lighting elements that Light in the ultraviolet or infrared wavelength range emit. Some embodiments thus include, for example five types of lighting elements, the infrared light, ultraviolet light and three primary colors of an additive color system, For example, the colors red, green and blue produce.

In 2 is a schematic plan view of a document inspection device 1 shown. Like technical features are indicated in all drawings with the same reference numerals. Shown is a two-dimensional array of cells 21 , Every cell 21 includes a detection element 22 which is photosensitive. The detection element is formed, for example, in CMOS technology. Every cell 21 additionally comprises at least one lighting element. In the illustrated embodiment, the cell comprises 21 three lighting elements 23 - 25 , which are designed as LEDs and can emit the colors red, green and blue. Furthermore, the cell comprises 21 electronic circuits for controlling an image acquisition and / or control of the individual lighting elements 23 - 25 and / or the detection element 22 ,

Become wavelength-sensitive detection elements used, the capture only a limited wavelength range, so can in a cell also several detection elements for different Wavelength ranges be provided.

In 3 is a schematic sectional view through a differently formed cell 21 ' shown. In a transparent substrate 31 is a detection element 22 ' educated. On a bottom is a non-transparent protective layer 32 educated. Below the substrate 31 are lighting elements 23 ' . 24 ' arranged, which are formed for example as TFT cells or LCD cells. A circuit 26 ' is below the detection element in this embodiment 22 ' educated. Such a design allows a higher integration density, since at least parts of the required elements can be arranged one above the other.

In 4 is schematically a detection array 41 shown. At the intersection points of each line a detection element is arranged in each case. In addition, there are two sub-arrays 42 . 43 represented by two different types of lighting elements. At the intersections of these sub-arrays 42 . 43 each lighting elements are arranged. The lighting elements of the two sub-arrays 42 . 43 differ with respect to the light that the respective lighting elements emit. The sub-arrays 42 . 43 together form a lighting array 44 , In the illustrated schematic embodiment, two illumination elements are associated with each detection element. Both the capture array 41 as well as the two sub-arrays 42 . 43 have an identical matrix-like shape. The individual lighting elements as well as detection elements can be considered to be arranged in columns and rows. In the illustrated embodiment, the column and row spacings are between the different arrays 41 - 43 and within each array 41 - 43 identical. In other embodiments, the capture array and the sub-arrays of the illumination device may have different column and row spacings. Within a subarray, however, the column spacing is preferably constant. The same applies to the line spacing, where the column spacing and the line spacing need not be identical. Likewise, embodiments are conceivable in which the sub-arrays have mutually different column and line spacing. For example, a sub-array, which includes lighting elements that emit ultraviolet radiation, have greater column and line spacing, provided that a uniform illumination of the illumination surface is ensured. The sub-arrays of lighting elements that emit visible light in the primary colors, on the other hand, are arranged at smaller row and column spacings to provide a high-resolution display device.

The Illustrated embodiments are merely exemplary Embodiments. It results for the skilled person that the individual lighting elements and detection elements are different can be configured. The individual characteristics of the different described embodiments may be arbitrary be combined together to carry out the invention.

1

Proofing device

2

casing

3

platen

4

top the platen

5

touch-sensitive Position sensing device

6

detector

7

of the Platen facing side

8th

double arrow

9

document

10

detecting surface

11

lighting device

12

illumination area

13

evaluation

14

Storage

15

control unit

16

interface

17

microprocessor

18

energy storage

21 21 '

cell

22 22 '

sensing element

23-25

lighting element

26 26 '

circuit

32

protective layer

41

Sensing array

42 43

Under arrays

44

Lighting Array

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• EP 0246481 A1 [0002]
• EP 0246481 [0002]
• US 5187596 [0003]
• US 5650864 [0004]

Cited non-patent literature

• - ISO / IEC 7810: 2003 I [0007]

Claims (21)

Document checking device ( 1 ), comprising a transparent support plate ( 3 ), a lighting device ( 11 ) for illuminating one in contact with the platen ( 3 ) ( 9 ), a detection device ( 6 ) for the visual capture of the illumination device ( 11 ) illuminated document ( 9 ), wherein the detection device ( 6 ) a plurality of detection elements ( 22 ), characterized in that the detection elements ( 22 ) in a two-dimensional acquisition array ( 41 ), the extent of which is at least one dimension of the document intended for 9 ) and a detection area ( 10 ) on the platen ( 3 ), and the lighting device ( 11 ) a plurality of lighting elements ( 23 - 25 ) in a two-dimensional illumination array ( 44 ) are arranged around a lighting surface ( 12 ) on the platen ( 3 ), the illumination area ( 12 ) the detection area ( 10 ) covered. Document checking device ( 1 ) according to claim 1, characterized in that a plurality of the illumination elements and a plurality of the detection elements ( 22 ) are formed on a common semiconductor substrate. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the detection device ( 6 ) several detection units each having a plurality of detection elements ( 22 ) and the illumination device ( 11 ) several lighting units each having a plurality of lighting elements ( 23 - 25 ) and in each case a lighting unit and a detection unit are formed on a common semiconductor substrate. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the plurality of lighting elements ( 23 - 25 ) different types of lighting elements ( 23 - 25 ), wherein the different types of lighting elements ( 23 - 25 ) differ in a property of the light generated by them. Document checking device ( 1 ) according to claim 4, characterized in that the property of the generated light comprises a wavelength, a polarization type, a polarization direction and / or an emission direction. Document checking device ( 1 ) according to one of claims 4 or 5, characterized in that the illumination device ( 11 ) at least three different types of lighting elements ( 23 - 25 ) which generate light in primary colors of an additive color system. Document checking device ( 1 ) according to one of claims 4 to 6, characterized in that the lighting elements ( 23 - 25 ) of each of the different types of lighting elements ( 23 - 25 ) in a sub-array ( 42 . 43 ), the illumination elements of each sub-array ( 42 . 43 ) the detection area ( 10 ) can illuminate with light of a property. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the lighting elements ( 23 - 25 ) with a control unit ( 15 ), which is formed, the individual lighting elements ( 23 - 25 ) individually. Document checking device ( 1 ) according to claim 8, characterized in that the control unit ( 15 ) is formed, by means of individually controlled lighting elements ( 23 - 25 ) to realize a graphic display. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the detection device ( 6 ) with an evaluation unit ( 13 ), which is designed to store the graphical data of the document ( 9 ), in particular a verification of the authenticity of the document ( 9 ). Document checking device ( 1 ) according to claim 10, characterized in that the evaluation unit ( 13 ) from the graphical data of the document ( 9 ) Extract information and check the extracted information against reference information stored in a database. Document checking device ( 1 ) according to one of claims 9 to 11, characterized in that by means of the graphical display, a result of the evaluation is graphically displayed or displayed. Document checking device ( 1 ) according to one of claims 7 to 12, characterized in that the sub-arrays ( 42 . 43 ) of the lighting elements ( 23 - 25 ) of the at least three different types that generate light in primary colors of the additive color system, each having a matrix-like configuration, in which the individual lighting elements ( 23 - 25 ) are arranged in rows and columns, wherein row and column spacings of the sub-arrays ( 42 . 43 ) are the same. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the detection elements ( 22 ) are arranged like a matrix in rows and columns. Document checking device ( 1 ) according to one of claims 7 to 14, characterized in that the row spacings between the rows of the detection array ( 41 ) are constant and the row spacings of the rows of the at least three sub-arrays ( 42 . 43 ) are the same. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the lighting elements ( 23 - 25 ) are formed as LEDs. 17 document checking device ( 1 ) according to one of the preceding claims, characterized in that the lighting elements ( 23 - 25 ) are formed as cells of a LED, OLED, TFT, LCD or plasma screen. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the detection elements ( 22 ) are formed on one or more substrates, which has through-holes, through which the light of the lighting elements ( 23 - 25 ), which are arranged on the side facing away from the support plate side of the substrate or the substrates. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the detection elements ( 22 ) are designed polarization-dependent. Document checking device ( 1 ) according to one of the preceding claims, characterized in that circuits for processing the detected signals of the detection elements ( 22 ) and / or for controlling the lighting elements ( 23 - 25 ) are formed on the substrate on which the detection elements ( 22 ) of the detection unit are formed. Document checking device ( 1 ) according to one of the preceding claims, characterized in that an energy store ( 18 ) is included for providing electrical energy. Document checking device ( 1 ) according to one of the preceding claims, characterized in that the support plate ( 3 ) with a touch-sensitive position detection device ( 5 ) is provided.