DE19846619A1 - Structured surface appearance quality determining equipment, evaluates electrical measurement signal from photosensor array to derive structure code characterizing structure-dependent characteristic of measurement surface - Google Patents

Abstract

In an illumination tube (2), light is focused towards the measuring surface (8). The light is reflected by the measuring surface towards a measurement tube (10). A photosensor array (12) outputs an electrical measurement signal based on the characteristics of the reflected light. A control unit evaluates the measurement signal to derive a structure code, which is a function of structure-dependent characteristics of the measurement surface. An Independent claim is also included for a method for determining the structured surface quality.

Description

The present invention relates to an apparatus and a ver drive to determine the quality of structured surfaces.

Under the quality of a surface or a structured Here, the physical properties of a surface should Surface are understood to be the appearance of a surface for the human viewer.

In particular properties such as structure, color, brightness of the Color, gloss, sharpness of image (DOI), glossy haze, upper surface textures and surface ripples (orange peel) etc. characterize structured surfaces.

The quality of the visible surfaces is essential property of everyday objects, such as for example furnishings and utensils, like cars and the like.

In the field of automotive technology, a lot of value is placed on the visu the impression of the visible surfaces. Hereinafter become the technical problems involved in the design of upper areas in the motor vehicle area arise, explained in more detail, without however, the present invention as applied in any in a way.  

Motor vehicle bodies are usually high provided glossy or metallic paint, their reflectivity or gloss value the corresponding values of other surfaces, such as B. furniture, is far superior. The high gloss of the use The varnish and the relatively large, flat surfaces require one extraordinarily careful preparation of the surfaces to be painted and a particularly careful application of the paint.

Various methods and devices are in the prior art and apparatuses known, e.g. B. in DE 44 34 203 A1 with which the visual properties and especially the Re flexion behavior of surfaces can be determined.

Furthermore, in the automotive industry in the interior of Motor vehicles ver a variety of structured surfaces works from natural substances, such as. B. wood or art consist of fabric.

The visual impression of structured surfaces depends essentially depends on the distinctiveness of the structure of the surface but also from the other optical parameters mentioned above Right.

The automobile manufacturers now employ a large number of Testers and use a variety of elaborate, large-scale Measuring devices that visually or automa Check the table to see if there are any quality defects on the surfaces Recognizing production. However, this method brings a whole Series of disadvantages.

The work of the visual inspector is very exhausting and demanding changes workrooms whose lighting conditions are always precisely defined are. Nevertheless, there were large differences in the rating of same surfaces determined by different inspectors because on the one hand the respective physiological impression of the examiner  Examiner is different, and secondly, eyesight of the individual auditor also from their respective physical Constitution depends.

It is therefore very difficult to achieve a lower quality to define a limit that is no longer acceptable can be.

It is also difficult for experienced examiners to determine the causes of an insufficient visual impression. Be The visual impression is particularly good with structured surfaces determined by a combination of different parameters, so that it is difficult, based on the observations made and Measurements e.g. B. Control values of an automatic painting change direction to improve quality.

Structured plastic surfaces are often characterized by a pre produced ge process in which the forms or pre rolls etc. are subject to wear. With increasing arrival The structure of the embossing shape and number of embossed surfaces thus the structure of the plastic surface is becoming less and less. The stamping tool can be replaced regularly Production to be optimized in terms of quality and quantity; however, the life of the tools used is at Fluctuations in the material composition or fluctuations in the Ambient conditions differ, so that the tools in general already exchanged, although their quality for Production of finished structured surfaces is still sufficient.

Are used to check the quality of structured surfaces auto matically working devices used to z. B. the gloss or the To determine the image sharpness of the surface, quanti tative numerical values can be obtained. A crucial disadvantage is however with the visual and also with the automatic test found that values for the examined optical properties  can be determined, but the user has no information about has the cause.

Another disadvantage of conventional measuring equipment is that it have a considerable space requirement, and therefore not from the user can be taken with you.

It is therefore an object of the present invention to provide a ver drive and a device of the type mentioned available supply, so that a reproducible evaluation of the Quality of surfaces and especially structured surfaces Chen can be done and that such physical quantities to measuring surface that are characteristic structure-related property of this surface is determined.

Another aspect of the task is to create a device create that small and light and so be create is that they easily mitgenom by an operator and without any additional tools for evaluating a surface can be used.

Another aspect of the task is a device for measuring to create visual properties which, despite the compact structure according to the previous aspect of the task of the Er finding the possibilities for measurement compared to those in the prior art Technology known devices is significantly expanded.

Another aspect of the task is to provide a method which is an advantageous detection of a characteristic structure-related property of surfaces.

According to the invention, this object is achieved by a device as defined in claim 1. The inventive method ren is the subject of claim 45.  

Preferred developments of the invention are the subject of Subclaims.

In the device according to the invention, a first opti device that has one or more light sources, Light at a predetermined angle on a measuring surface tet, which is part of the surface to be measured.

With a measuring at a second, predetermined angle to this area-oriented, second optical device, the one or has multiple photosensitive photosensors, that will reflected light from the measuring surface.

This photo sensor or these photo sensors, the minde at least have a light-sensitive surface, give an electri cal measurement signal, which characterizes the reflected light is realistic, the first and the second optical device are such that the reflected light through the structure this measuring surface is influenced.

An evaluation device is in the device according to the invention arranged, which is provided for controlling the measurement sequence and the at least one processor device and at least one Has storage device and the reflected light evaluates and derives at least one structural key figure, wel che at least one of the structural properties of these Characterized surface.

An output device in the device according to the invention is arranged, is used to output the measured values.

The evaluation device evaluates one in the memory device tion stored program the measurement signals and stores in a preferred development of the device according to the invention  the measurement signals and / or the measurement values in this memory device tung.

In a further preferred development of the invention Devices are a lot in the second optical device Number of photo sensors arranged in rows and / or Spal ten can be arranged.

In contrast to conventional devices, the device according to the invention the photosensors on a common seeds are arranged. The individual photo sensors can also by interconnecting photosensitive surfaces on one common substrate are formed, the area of each photosensitive sensor is selected or selectable so that it in the measuring device a predetermined angular range of the reflect xionswinkel corresponds.

The device according to the invention has considerable advantages:
An essential prerequisite for controlling the production process in the production of structured and unstructured surfaces is the determination of the optical quality or the visual impression of the surface. By analyzing the light reflected on the surface, a structural key figure is derived that describes the quality of the surface. A key figure for the structure of structured surfaces is not determined by conventional visual or automatic measuring methods.

This is particularly advantageous because the profile of the structure is one structured surface essential to the overall visual impression contributes to this surface.

When using embossing, casting or other procedures below are the shapes used a wear that u. a. of the  Number of manufactured, structured surfaces depends. Next the number of manufactured components with structured surfaces but also play environmental conditions such as humidity, mate rial and air temperature play a crucial role in quality the surface to be manufactured.

In conventional manufacturing processes, the ones used Forms after a certain number of embossed or cast Components or who are replaced after a certain period of time to ensure a consistently high quality of construction secure parts.

This procedure leads to an unnecessarily high expenditure, since often also tools with sufficient quality who are replaced while, on the other hand, it also happens that through environmental flows or material inhomogeneities or differences in the plant are worn out before the scheduled time of change.

One way to avoid having too many rejects is regular checks. To do this, the production process must Checking of the tools are stopped, so that costs playful downtimes result.

With the device according to the invention it is possible to simply the Qua quickly and reliably during ongoing production lity of structured surfaces to determine, so that a too casual wear of the tools can be determined at an early stage can and avoid unnecessary downtimes of the production plant that will.

Another advantage of using the pre according to the invention Direction is that unnecessarily frequent changes of the work used witnesses, shapes and embossing rolls and the like leads to lower production costs.  

Another major advantage is that the invention Device is small and so mitge by the user at all times can be taken.

Therefore, the device according to the invention is also suitable for Final inspection in poorly accessible places or indoors from Z. B. motor vehicles, where a variety of structured upper areas is used.

Another advantage of such a small device is that even on concave or convex curved surfaces the qual can be determined easily and reliably.

It is also advantageous that the device according to the invention different places on a surface to be examined can be measured quickly and easily and so the quality distribution over a surface or reproducibility can be tested.

In a preferred development of the device according to the invention tion has at least a first part of this from this first optical device emitted light a light pattern. The first optical device can ent a pattern device hold. That of this at least one light source of this first optical device emitted light will continue at this formation of the device according to the invention at least partially blasted onto this sample device. That through these patterns direction transmitted light is made according to the pattern of Pattern device influenced in amplitude and / or phase.

In a further preferred development of the invention The device has that emitted by this pattern device Light pattern at least one light / dark edge, or a lot number of light / dark edges, with a further next formation of the device according to the invention at least part  this multitude of light / dark edges at least in sections runs parallel to each other.

The pattern of this pattern device can be symmetrical to the opti rule the axis. In the event that the broadcast Light pattern has a variety of light / dark edges, can the individual light / dark edges a straight, circular or have a sinusoidal shape.

In a preferred development, at least part of this is Variety of light / dark edges grid, cross grid or arranged in a circle.

The projection of a light pattern onto the surface to be examined area is particularly advantageous since the evaluation of the data from the surface to be examined or the measuring surface reflected Light pattern conclusions on the quality and structure of the measurement area to be examined allowed.

It is possible that the light pattern does not have sharp transitions from has light to dark, but the intensity of the projected th light influenced sinusoidal or sawtooth-shaped.

In a further preferred development of the invention The device has a first part of one of these first opti the light emitted by this device, while a second part without a light pattern on the measuring surface is aimed.

But it is also possible that in the Vorrich invention tion, the pattern device can be switched on, so that a deviation Selective measurement with light pattern and without light pattern is possible.

It is possible that this pattern device z. B. an LCD Has facility in which individual areas or individual  Shutter pixels to different light patterns as required can be tet, so that the light pattern quickly and easily on the given requirements are adjusted or switched off can.

By evaluating the signal of this at least one photo sensor, which has at least part of the reflected light pattern takes, a structural key figure from this evaluation device be determined which at least for a structure-related egg characteristic of this surface is characteristic.

In a further preferred development of the invention The device determines this evaluation device at least for egg part of this large number of photo sensors an increase in the elec trical and / or digital measurement signal by a difference of electrical and / or digital measurement signal of the photo sensor with this electrical and / or digital measurement signal of the next Fo tosensors is formed in this row and / or column, or in the differences in the electrical and / or digital measurement signal this photo sensor with this electrical and / or digital Measurement signal of at least part of the directly or diagonally adjacent beard photo sensors are formed.

This is particularly advantageous because the slopes of the measurement signals and in particular the slopes of the measurement signals when irradiated with a light pattern are suitable for a structural key figure to derive which for at least one structure-related property shaft of the measuring surface to be examined is characteristic.

In a further preferred development of the invention This evaluation device determines at least one device Average of at least part of these gradients of the Messsi gnale of these photo sensors and determines at least one of them average this characteristic structural index for  this at least one structure-related property of this waiter area.

A histogram can also be determined from these gradients in which for predetermined and / or selectable areas Slope above the number of these slopes in the corresponding Intervals or areas is applied. With the formation of the The center of gravity and / or the mean value of the slopes can be a characteristic structural key figure in this evaluation device which are derived from the structure-related properties characterized this surface.

This preferred development of the device according to the invention is particularly advantageous because by determining at least one egg part of the slopes and by averaging a characteristic structure quickly and reliably key figure can be determined for this measuring surface.

Rounded surface structures, such as z. B. in use of worn or worn tools in production structured surfaces emerge, reflect on them Surface projected light is more diffuse than surfaces with sharp distinctive profile.

By using such a further development of the Invention According to the device, it is possible to own the structure to determine.

In a further preferred development of the invention Device are used as optical parameters in addition to this character structural key figure at least one, two, three or be more characteristic, optical parameters of this measuring surface Right.  

In preferred developments of the invention, the gloss (Engl. gloss) or the Schleierglanz (Engl. haze) or the Abbil distinction of image DOI or a representative tative measure of the typical wavelength and its amplitude (English orange peel) the topology of the layer thickness of this measuring surface che determined.

The orange peel is determined in a predetermined manner Wavelength interval; the evaluation to determine the orange However, peel can also be used in two or more wavelength ranges consequences. It is also possible to change the color of the measuring surface or to determine the brightness of the color.

In a further preferred development of this invention, who in addition to the structural key figure, there are also other of the above characteristic optical parameters determined.

Such a development of the device according to the invention is particularly advantageous because with this small-sized device u. U. all interesting, visual and physical properties th of this measuring surface can be determined.

In an advantageous development of all described above benen exemplary embodiments is a third optical device arranged, which has at least one light source and light with a given spectral characteristic, wel ches directed at this measuring surface at a predetermined angle is.

In the preferred further developments of the inventions mentioned above device according to the invention, the predetermined angle at which the light emitted by the first optical device this measuring surface is aligned and / or the predetermined win kel, under which the second optical device that of this Measuring surface reflects reflected light, and / or the predetermined  Angle at which that from the third optical device radiated light is aligned to this measuring surface, freely be made and includes in particular the angles 5 °, 10 °, 15 °, 20 °, 30 °, 45 °, 60 °, 75 °, 80 ° and 85 ° between the normal of the Measuring surface and the corresponding angle. However, it was on it pointed out that angles other than those mentioned here are also possible are.

In a further preferred development of the invention this emitted by this third optical device Light directed at the surface at such an angle that this is directly from the measuring surface according to Fresnel's Re reflected light directed towards this measuring surface has a different angle than the angle between this measuring surface and that reflected by this measuring surface Light emitted by this first optical device is emitted, so that the second optical device or the Fo sensors essentially that of the third optical device device emitted light and diffuse from this measuring surface reflec takes light.

This at least one light source of this third optical one directions can be one, two and particularly preferably three lights have radiating elements whose light emits in the th spectral characteristic so different that the emit tated wavelength ranges are different.

The emitted wavelength ranges of these light emitting Elements can become visible in the light spectrum overlap at least partially, and in another preferred Further development of the device according to the invention are the emit ted, spectral characteristics of these light emitting Elements linearly independent of each other.  

In a further preferred development of the invention Devices are at least two, preferably three or more fo sensors designed in such a way that they differ in their spectral range Distinguish characteristic, so that as an optical parameter water measuring surface the color of the reflected light can be detected.

In another preferred development of the invention The device has at least one photosensor, at least two preferably three or more photosensitive elements, the elec trical output signals can be detected individually and which are in ih rer spectral characteristics, so that the color of the reflected light from this measuring surface can be detected.

A further development of the device according to the invention that he possible, the color of the light reflected by this measuring surface it is particularly advantageous to record, since the color and the hel lightness essential characteristics of surfaces and also of structured surfaces.

In further preferred developments of the invention Device are opti in this first and / or third equipment one or more light emitting diodes or laser light sources arranged.

At least part of that from this first optical device and / or this third optical device is broadcast Light is essentially parallel, divergent or convergent.

In a further preferred development of the invention The device emits this first and / or third optical device tion at least one light spot with a predetermined diameter perpendicular to the direction of propagation of the emitted light or at least one light strip with a predetermined length and width perpendicular to the direction of propagation of the emitted light.  

This light pattern projected by the first optical device ster can also be made of different light spots or strips of light consist.

It should be noted that this is at least an optical Characteristic or this structural key figure also from the electrical and / or digital measurement signals of these photo sensors determines who which can reflect these two from this measuring surface th part without light pattern this from this first optical input direction of light emitted.

In a further preferred development of the invention The device is in the immediate vicinity of at least one Light source of this first optical device and / or this at least one light source or at least one light radiating element of this third optical device and / or this at least one photo sensor or this little least one photosensitive element at least one temperature arranged measuring device, which for determining the character static temperature of the respective light source, emit light the elements, photo sensors or light-sensitive elements is to see that a temperature-corrected determination of this we at least one structural characteristic and / or this at least one optical parameter can take place.

The determination of the characteristic temperatures of the light source len and photo sensors is particularly advantageous because these electri working facilities depending on temperature and by a Temperature-corrected determination of the parameters and parameters Reproducibility of measurements is increased; because to increase the measuring time or with changing measuring apparatus the tempe rature and their distribution within the invention change direction.  

In a further preferred development of the invention at least part of the course of the on this plurality of fo to the sensors shown in the light pattern. By a deviation The measured course from the ideal course can be a cha characteristic profile height characteristic of this measuring surface is determined become.

In a particularly preferred development, the course we at least one light / dark edge in sections on this Variety of photo sensors or on the CCD chip determined.

Will a light or dark line on a surface to be examined projected area, which is a rectangular profile with a profile height h has a spatial separation of the reflex Line takes place on the CCD chip of the second optical device.

The part reflected from the lower edges of the rectangular profile The dark or light lines are spatially parallel sets to those reflected on the top edges of the right corner profile are reflected.

The reflected image of an ideal, rectangular structure The surface is two dashed light or dark lines on the CCD chip.

With the known angle of incidence and reflection and the distance These two dashed lines on the CCD chip can change the height of the profile can be determined at any location on the measuring surface.

When measuring non-rectangular surface profiles can be analogous to the corresponding geometric relationships Profile height characteristic of this measuring surface can be determined.  

The determination of a profile height parameter is particularly advantageous liable, because when the manufacturing tools wear out, the Profile height of the manufactured components can decrease.

In a further preferred development of the invention this structural key figure using a triangulation method true, this determination of this structural key figure finally or additionally by means of this triangulation procedure can take place. It should be noted that one the common triangulation methods as used in the prior art nik are known, can be used.

One example is the one from the American patents US 5,546,189 and US 5,744,793 shown triangulation pointed out, hereby part of the disclosure of the present Invention.

In a further preferred development of the invention The device is in contrast to that in U.S. Patent 5,546,189 Process produced no or not exclusively a gray value determines which is representative of the height of the measuring surface is at the measuring location, but it will be the surface height at the measuring location in the greatest possible precision.

In a further preferred development of the invention, ei ne additional optical device with at least one photo sor provided, which at a predetermined angle to this Measuring surface is aligned. In a particularly preferred way terbildung is this additional optical device in the level ne arranged by the measuring point, the second optical on direction and the third optical device is spanned, and it is particularly preferred that the angle at which this additional optical device that receives reflected light, is equal to the angle at which the second optical device the reflected light picks up so that the second and the too  additional optical device symmetrical to that of the first optical device or symmetrical to that of the third op table device are arranged emitted light.

In a further preferred development of the invention the intensity and location of the point of impact of the reflected Intensity on this second optical device and this determined additional optical device, and especially before A characteristic location is added by this evaluation unit characteristic value for the location of the measurement and the measured intensity in this storage device, and this evaluation unit determines a characteristic distance parameter for the Ab stood at the measuring point on the surface to be examined and fed saves this in this storage device.

In a further preferred development of the invention the first optical device has a scanning device, which scans the surface to be examined in such a way that that of the his first optical device emitted light temporally sequentially scans the surface to be examined.

This evaluation device particularly preferably determines with these Distance parameters and these location parameters at least one die at least one structural key figure.

In a further preferred development of the invention The device becomes at least a quantitative slope value for the steepness of the structure of the surface to be examined certainly.

In a further preferred development of the invention does this evaluation device agree at least one quantitative one Sharpness value for the sharpness of the edges of the examined Surface.  

These developments are particularly advantageous because with the Ab use of tools to produce the structure of the surface of the ling components decreases and especially through wear and tear wear decreases the steepness of the structure and in particular also the sharpness of the edges decreases, as the wear increases Rounds off the profile of the tool.

In a further preferred development, this we at least one structural key figure and at least one of the named characteristic optical parameters (gloss, fog, Sharpness, orange peel) an evaluation structure key figure derived which at least for part of the visual eigen is characteristic of this surface.

When evaluating surfaces and especially struktu The visual impression depends not only on the surface Expression of the structure, but also of the others mentioned characteristic optical sizes. For example, at particularly smooth and highly reflective surfaces conditions of the manufacturing process particularly high, because on such The human eye surfaces even the smallest disturbances, uneven and perceive changes. In vehicles with so-called called "metallic" painting, it is almost impossible to paint on a large area to repair paint damage so that this Damage remains invisible to the viewer.

In contrast, the requirements for matt and weak reflective surfaces to the coating quality of the paint and the underlying surface considerably less.

During surface roughness and orange peel even in the slightest Measure the physiological feeling of high-gloss surfaces disturbing the viewer, far greater roughness effects and surface ripples with weakly reflecting and mat areas on the visual impression of a viewer only  little or not at all. For structured surfaces, this is the visual impression due to the structure is less dependent on the surface roughness, the gloss or the other optical Parameters.

Therefore, according to this preferred development of the invention at least one evaluation structure key figure and at least one of the characteristic quantities mentioned, which is a measure represents the quality of the measuring surface.

In a preferred development of the invention, this becomes Characteristic value for the gloss of the measuring surface and this structural key figure An evaluation structure key figure is formed such that for areas with low gloss even with a non-ideal structural index a sufficient or satisfactory evaluation structure key figure is formed.

In a further preferred development it is provided that this valuation structure key figure is formed such that, for. B. a higher gloss compensates for a poorer structural index, so that this valuation structure key figure is qualitatively sufficient result.

In a further preferred development it is provided that for at least two or all of the optical quantities mentioned Shine, fog, sharpness, orange peel a review tion structure index is formed or that of two or more of the mentioned characteristic sizes (gloss, veil gloss, Sharpness, orange peel) and this structural key figure one Evaluation structure key figure is derived, which for the visu ellen impression of this measuring surface is characteristic.

The formation of at least one valuation structure key figure from the water at least one structural key figure and at least one of the characteristic optical quantities, such as gloss, etc., are special  advantageous because it is particularly simple and automatic or automated determination of the quality of the examined Surface is possible.

In a further preferred development of the invention Device is at least a lower or upper limit for this at least one structural key figure and / or this at least one ne characteristic optical parameter and / or at least this an evaluation structure key figure can be defined, for which Exceeding a message on this output device or a Alarm signal of an acoustic or optical type is issued.

In a further preferred development of the invention, the at least one limit value by measuring at least one ref boundary surface automatically determined. It is Z. B. possible that a two or more rated reference surfaces of different quality Lity can be measured, advantageously at least one die high quality and at least one white surface tere is of insufficient quality.

Through such a partially automated calibration of this device device can quickly and reliably measure different measuring points on one Surface or various surfaces to be examined leads.

Another preferred development is an on or off switch arranged.

Furthermore, an on this device according to the invention can be provided device, this u. a. intended for this may be that the user is a type identifier for the type of measuring surface, subsequent measurements with Reference to this type code from this evaluation device evaluated and stored in this storage device.

In a further preferred development of the invention, the User when switched on by an acoustic or optical Si  be prompted to enter a type in this input device Enter the identifier for the surface type to be measured, whereby in a particularly preferred further training of the users at any time change the surface type by entering another type code to which the subsequent measurements refer.

Entering or selecting a type code before the measurement nes certain surface type is particularly advantageous because in the Evaluation of different surface types the individual parameters ne different meaning and when forming an evaluation structure turkennummer have a different weighting.

In a further preferred development of the invention, the User for each measurement by entering the user Assessment number in this input device according to this measuring surface evaluate his physiological impression. This user Assessment number is particularly preferred together with this little At least a characteristic, optical parameter and this little at least one structural key figure and this at least one evaluation structure code permanently stored in this storage device, the range of values of this user rating number at least two different quality values, the "good" and "bad" ent speak, includes.

In a further preferred development of the invention, we at least a part of these stored in this storage device User assessment numbers with associated parameters and parameters the corresponding measurements for automatic determinations at least one of these at least one limit for this type used for the surface to be examined.

In a further preferred development of the invention The device essentially takes this evaluation device into account all in this storage device for this type identifier of the measuring surface filed user assessment numbers and the corresponding parameters and parameters and structural parameters for Determining this at least one limit value and determining the  Weighting factors, which are used to determine the evaluation structure indicator are used so that these weighting factors and at least one limit with increasing number of measurements be adjusted in such a way that this valuation structure key figure matches the vi customized impression of the user is adjusted.

This preferred development of the invention is particularly advantageous liable, since this device is used to determine these parameters and Characteristic values and this evaluation structure key figure is learnable and based on an expert system, the reliability of the Be this at least one evaluation structure key figure matches the Number of measurements increases.

In this preferred development of the invention, it is also provided that in determining these limits and weight not all measured and stored values for the This type identifier can be used because the physiological zu stood the user affects the evaluation of this measuring surface, and due to incorrect input of incorrect user ratings unwanted limit values and weighting factors can be determined nen.

It is possible e.g. B. that with a variety of existing knives results a certain percentage of z. B. 5% or 10% in the Formation of these weighting factors and these limit values unaffected remain visible, with the selection of those not taken into account Values are made using known, statistical methods.

This development of the invention is particularly advantageous because too in the event of incorrect input of incorrect user assessment numbers, these remain largely disregarded, so that by the learners ability of this evaluation device determines the reliability of the automatically determined valuation structure key figures with increasing Number of measurements increases.

In an advantageous development of all described above Ben exemplary embodiments, this device is relative to the measurement  shift surface in a substantially equidistant direction bar, and a distance measuring device is provided, which quantify this relative shift. In this Spei chereinrichtung the along predetermined measurement thresholds structural characteristics and / or characteristics measured on this surface tical optical parameters and / or evaluation structure indicators saved.

In a further preferred development, at least one measurement is wheel provided, which during the measurement on the to be measured Surface is placed and between the relative movement between the device and the surface to be measured, whereby this at least one measuring wheel is connected to a rotary encoder can be, which outputs an electrical rotation angle signal, wel ches is representative of the angle of rotation traveled by the measuring wheel.

This preferred development of the invention is particularly advantageous sticky, because surfaces to be examined z. B. systematically about the entire surface can be measured.

In the preferred development of the invention, in which a A plurality of photo sensors are arranged, is particularly preferred Usually a CCD chip is used, which is used in another, before Preferred development of the invention can be designed as a color CCD chip can.

When using a two-dimensional CCD chip, a two-dimensional nales image of this measuring surface in the second optical device mapped onto the CCD chip.

In a preferred development of the invention, the Measurements or before the start of each individual measurement a dark image are recorded and the values are averaged. When measuring the picture taken with lighting, also averaged and away subtracted the mean value of the dark image. It becomes a value for the Contrast of this image determines. With the mean values of the dark bil  of the illuminated image and the value for the contrast Normalized brightness of the measured image.

The further evaluation takes place with the standardized values or with the normalized picture.

In a further preferred development of the invention the evaluation using one or more Fourier transforms. Be The spatial frequency coefficients are particularly preferred for each line determined from a Fourier transform of this line and the Spatial frequency coefficients for the entire image are from the Mit of the frequencies of all lines.

In a further preferred development of the invention This structural characteristic value is created using a conventional method determined for roughness measurement of surfaces such. B. in DIN 4768 (Edition 1990-05), ISO 13565-1 (edition 1996-12) or ISO 13565-2 (Edition 1996-12), which are therefore part of the disclosure the.

It should be noted that the interaction of the individual Features according to the invention in any combination is moving. In particular, the independent and dependent claims disclosed feature combinations under way preference of one or more features. For the specialist it can be seen that about the execution shown here also play a variety of other modifications and designs are conceivable that are covered by the invention. The he In particular, the invention is not only limited to those presented here presented embodiments.

Further advantages, features and possible uses of the present ing invention result from the following description of Embodiments in connection with the drawings.  

In it show:

Fig. 1 shows a section of a first embodiment according to the present invention;

Fig. 2 shows another embodiment of a sensor element, wherein the zoom drawn to the light measurement areas can be varied;

Fig. 3 shows another embodiment of a sensor element, in which seven photosensors are formed with the light-sensitive surfaces;

Fig. 4 is a diagram showing lighting the reflection behavior at Be gives a light pattern, wherein the ideal reflection angle is plotted on the ordinate with respect to the measured light intensity and the abscissa the angular deviation;

Fig. 5 sters an image of the image projected on the measuring surface Lichtmu,

Fig. 6 shows the basic circuitry structure of a measuring device, as it is to be used in the exemplary embodiments according to FIGS . 1-5; and

Fig. 7 shows another embodiment of the invention, which is also suitable for further measurements.

A first embodiment of the invention will now be described with reference to FIG. 1.

The measuring device shown schematically in the figure for determining the quality of structured surfaces has a housing in which a first exposure tube 2 is arranged.

In this exposure tube, a light source 3 is arranged, schematically indicated, an aperture 4 , a Lichtmustereinrich device 6 and a lens device 5th

The light emitted by the punctiform light source 3 is limited in its aperture by the aperture 4 and strikes the light pattern device 6 . Depending on the embodiment, a partially transparent light pattern plate 9 can be arranged in the light pattern device 6 , in which the phase and / or the amplitude of the incident light is influenced in such a way on part of the illuminated surface that the transmitted light has a characteristic light pattern. In this exemplary embodiment, the amplitude of the light emitted by the light source 3 is influenced by light / dark edges on the light plate 9 .

Furthermore, the emitted light is bundled by the lens 5 and strikes the measuring surface 8 through the opening 7 . The light is reflected by the measuring surface 8 and enters the measuring tube 10 , which also has a lens 11 , an aperture 12 and the actual sensor 13 .

The reflection measuring device also has a (not Darge )) control device through which the operation of the pre Direction is controlled and an also not shown pointing device through which the measured structural parameters and characteristic optical parameters are displayed.

In FIG. 2, the sensor is shown a further embodiment. This embodiment is constructed with the exception of the sensor as in Fig. 1. Fig. 2 shows the sensor device 20 , in which a plurality of photosensitive elements 21 is arranged in rows and columns.

A CCD chip is used in this example. On the surface of the CCD chip, individual surface elements are interconnected to different photosensors 22 , 23 , 24 , so that only the signals from these photosensors 22 , 23 , 24 are present during the measurement.

It should be noted that the interconnection different surface elements for photo sensors Have measurement geometries realized. Furthermore, for measurement not all surface elements are used.

In Fig. 3, another embodiment of the Sensorein direction is shown. The further construction and operation of this device is carried out in the same way as in FIG. 1.

FIG. 3 shows the sensor device 30 which, as in the exemplary embodiment according to FIG. 2, is designed as a CCD chip.

Different photo sensors 31 , 32 , 33 and 34 are formed on the surface of the CCD chip by connecting individual surface elements. The interconnection of individual surface elements to photo sensors can quickly and easily according to different measurement standards, such as. B. the American ASTM E 430 can be measured.

In a further exemplary embodiment, the basic structure is the same as that of the exemplary embodiment according to FIG. 1, but no light pattern is projected onto the measuring surface. A CCD chip is used as the sensor device, with which all surface elements are measured individually.

In the diagram according to FIG. 4, the measured light intensity is plotted on the ordinate and the angular deviation with respect to the ideal reflection angle is plotted on the abscissa. The measured intensity is highest in the area of the ideal reflection angle and then decreases with increasing angular distance. The reflection behavior on the surface can be assessed in a simple manner from the curve so conceived.

It is also possible to derive the characteristic values from the curve, which, according to the various standards, the reflection behavior of Mark surfaces.

In FIG. 5, which is represented by a measurement area on the sensor device reflected image. The light pattern 50 has dark edges 51 and light lines 52 . A second part of the reflex 53 has no light pattern.

With increasing roughness, the contrast in the light pattern decreases, while a poorer shine affects the intensity. Orange peel leads to distortion of each dark and bright lines, and a textured surface leads in the case a rectangular profile to offset the individual lines in the area of the wells. In the case of sawtooth or triangular profiles, the corresponding sections correlating inclinations of the lines be determined.

The intensity and contrast of the captured image evaluated, and there are the gradients in the area of Lichtmu determined. By averaging the gradients, a characteristic measure for the structure of the measuring surface determined.

FIG. 7 shows the basic, cleavage-related design of a measuring device, as is to be used in the exemplary embodiments according to FIGS. 1-6.

The basic measurement set-up is for all shown execution play the same; only the programming differs depending on the ver sensor type.  

The measuring device has a total of a control device 60 which contains a commercially available microprocessor which is controlled by a program which is stored in a memory 61 . The communication of the control device 60 with the user serves an input device 62 which contains a number of switches in order to start the operation of the control device and to be able to switch between individual operating modes (in the corresponding exemplary embodiments). Furthermore, the user can enter a type identifier for the structured surface to be measured into the input device 61 , to which subsequent measurements relate.

In addition to the microprocessor, the control device has / Output devices on which the connection of the tax serve direction with the individual components of the device.

The control device is connected to the light source 3 and the sensor 14 . The results of the measurement are shown on a display 65 , which is preferably designed as an LCD display. A connection to an external computer 76 is provided for the further evaluation of the measurement; the measurement results are preferably also stored in the memory device 61 .

The measuring device is powered by a battery (not shown) powered.

Overall, the measuring device is preferably arranged in a housing 1 , which has approximately the size of a paperback.

Another embodiment of the present invention will now be described with reference to FIG. 7.

In this exemplary embodiment, the device is arranged overall in a housing 100 which has an opening 101 with which the device is placed on the surface to be measured.

In contrast to the previous exemplary embodiments, the device is not placed directly on the surface, however, but by means of (schematically indicated) at least two rubber rollers 103 , 104 or at least four rubber wheels 103 , 104 , which are rotatably mounted (not shown) in the housing 100 .

At least one of the rubber wheels or rollers is provided with a distance measuring device (not shown) which detects the angular movements of the rubber wheels 103 , 104 and outputs a representative electrical signal.

The device also has a first optical device 110 , in which a point-shaped light source 111 and a lens 112 are arranged. This first optical device 110 is aligned such that the optical axis is aligned at a predetermined angle (45 ° in the example shown) to the surface 115 to be measured.

At a second predetermined angle (here also 45 °), a second optical device is arranged, which has a Linsenein device 121 , an aperture device 122 and a measuring sensor 123 aligned perpendicular to the optical axis, which in this embodiment is designed as a color CCD chip .

On a third optical device 130 , three light-emitting elements 132 , 133 and 134 are arranged, which are embodied here as LEDs, each of which has a different spectral characteristic, ie which emit light with different color characteristics.

In the exemplary embodiment shown here, this is not the case LEDs emitted light essentially perpendicular to the un searching surface.

The light emitted by the first and the third optical device is reflected on the surface to be examined 115 and partly falls on the photosensor or color CCD chip 125 .

Since the light-emitting elements 132-134 emit light with different color characteristics in the visible range of the spectrum, it is possible to determine a color characteristic for the surface to be examined.

Claims (45)

1. Device for the quantified determination of the quality of structured surfaces with:
a first optical device with at least one light source, the light of which is directed at a predetermined angle onto a measuring surface which is part of the surface to be measured,
a second optical device which is aligned at a predetermined angle to this measuring surface and which receives the light reflected from the measuring surface, this second optical device having at least one photosensor with at least one photosensitive surface, this at least one photosensor being an electrical one Outputs measurement signal which is characteristic of the reflected light;
an evaluation device which is provided for controlling the measurement sequence and which has at least one processor device and at least one memory device;
an output device;
wherein this first optical device and this second optical device are such that this reflected light is influenced by the structure of this measuring surface, and
wherein this evaluation device evaluates this reflected light and derives from it at least one structural characteristic number which characterizes at least one structure-related property of this surface. 2. Device according to at least one of the preceding An sayings, characterized, that this evaluation device via a in this Spei chereinrichtung stored program these measurement signals evaluates and / or stores in this memory device. 3. Device according to at least one of the preceding An sayings, characterized, that this second optical device a variety of Fo includes sensors in rows and / or columns are arranged. 4. Device according to at least one of the preceding An sayings, characterized, that at least a first part of this from this first op table equipment emitted light a light pattern having. 5. Device according to at least one of the preceding An sayings, characterized, that this from this first optical device beamed light pattern at least one light / dark edge or has a variety of light / dark edges. 6. Device according to at least one of the preceding An sayings, characterized, that at least part of this multitude of bright / Dark edges at least in sections parallel to each other that runs. 7. Device according to at least one of the preceding An sayings, characterized, that at least part of this multitude of bright  / Dark edges grid or cross grid or circular are arranged. 8. Device according to at least one of the preceding An sayings, characterized, that this first part of this from this first optical Set up emitted light on this light pattern points and that a second part without light pattern on this Measuring surface is directed. 9. Device according to at least one of the preceding An sayings, characterized, that this evaluation device for at least part this large number of photo sensors an increase in the electri rule and / or digital measurement signal determined by a Difference of the electrical and / or digital measurement signal this photo sensor with this electrical and / or digita len measurement signal of the next photo sensor in this row and / or column is formed. 10. Device according to at least one of the preceding An sayings, characterized, that this evaluation device for at least part this large number of photo sensors the slopes of the elek trical and / or digital measurement signal determined by the Differences in the electrical and / or digital measurement signal of these photo sensors with the electrical and / or digital Measurement signals of all neighboring photo sensors are formed the. 11. The device according to at least one of the preceding An sayings, characterized, that this evaluation device has at least an average at least part of the slopes determined and from it  this characteristic structural indicator for this little most of all a structure-related property of this surface certainly. 12. The device according to at least one of the preceding An sayings, characterized, that one, two, three or more characteristic optical Characteristics of this measuring surface can be determined. 13. Device according to at least one of the preceding An sayings, characterized, that this characteristic optical parameter is the gloss or the glossy haze or the image sharpness (DOI) of the Measuring area is. 14. The device according to at least one of the preceding An sayings, characterized, that this characteristic optical parameter is a repr sentative measure of the typical wavelength and its Amplitude (orange peel) of the topology of the layer thickness water measuring surface in a predetermined wavelength interval is, this evaluation also in two or more waves length ranges can be done. 15. Device according to at least one of the preceding An sayings, characterized, that this device with a third optical device has at least one light source and light with a predetermined spectral characteristic, which directed at this measuring surface at a predetermined angle is. 16. The device according to at least one of the preceding An sayings, characterized,  that this predetermined angle at which that of which he most optical device emitted light to this Measuring surface is aligned, and / or that this predetermined angle at which the second opti cal device reflected by this measuring surface Absorbs light, and / or that this predetermined angle at which that of the third optical device emitted light to this Measuring surface is aligned, is / are adjustable and in particular the angles 5 °, 10 °, 15 °, 20 °, 30 °, 45 °, 60 °, 75 °, 80 ° and 85 °. 17. The device according to at least one of the preceding An sayings, characterized, that this from this third optical device shone light on the surface at such an angle che is directed that that directly from the measuring surface directionally reflected according to Fresnel's reflection Light at a different angle to this measuring surface points as the angle between this measuring surface and that of this measuring surface directed reflected light, which from this first optical device is broadcast. 18. Device according to at least one of the preceding An sayings, characterized, that this at least one light source of this third opti rule at least two, preferably three light has radiating elements, the light of which is reflected in the emits spectral characteristics in such a way that the emitted wavelength ranges are different are. 19. Device according to at least one of the preceding An sayings, characterized,  that these emitted wavelength ranges of this light emitting elements in the visible area of the Light spectrum at least partially overlap, and that the they emitted spectral characteristics of these lights radiating elements are linearly independent of one another. 20. Device according to at least one of the preceding An sayings, characterized, that at least one photosensor at least two, preferably has three or more photosensitive elements, the elec trical output signals are individually detectable and the differ in their spectral characteristics, so that the color of the right as an optical parameter of this measuring surface reflected light is detectable. 21. Device according to at least one of the preceding An sayings, characterized, that this at least one light source of this first opti and / or this third optical device or more light emitting diodes and / or laser light sources points. 22. Device according to at least one of the preceding An sayings, characterized, that this first and / or third optical device device emits essentially parallel light. 23. The device according to at least one of the preceding An sayings, characterized, that this first and / or third optical device in essential divergent or convergent light shine.   24. The device according to at least one of the preceding An sayings, characterized, that we first and / or third optical device at least one light spot with a predetermined diameter perpendicular to the direction of propagation or at least one Streaks of light with a predetermined length and width perpendicular emits to the direction of propagation. 25. Device according to at least one of the preceding An sayings, characterized, that at least one of these at least one optical characteristic quantities from the electrical and / or digital measurement signals of these photo sensors is determined, which of these from the Measuring area reflected second part of this he most optical device record light emitted. 26. Device according to at least one of the preceding An sayings, characterized, that in the immediate vicinity of this light source (s) this first optical device and / or this light source (s) of this third optical device and / or this at least one photo sensor at least one tempe raturmeß device is arranged, which for determination the characteristic temperature of the respective light source le (n) and / or the respective photo sensors is provided, thus a temperature-corrected determination of this little at least one structural characteristic value and / or at least this an optical parameter can take place. 27. The device according to at least one of the preceding An sayings, characterized, that at least part of the course of the image of this we at least one light / dark edge on this multitude of Photo sensors is determined and by a deviation from  ideal course of this measured course a character The profile height characteristic of this measuring surface is determined becomes. 28. Device according to at least one of the preceding An sayings, characterized, that this structural key figure by means of a triangulation ver driving is determined. 29. Device according to at least one of the preceding An sayings, characterized, that at least one of these at least one sensor Intensity of this first optical device blasted and right from the surface to be examined inflected light determined, and that this evaluation unit a characteristic location characteristic for the location of the mes solution in this storage device and that this Evaluation unit a cha from this measured intensity characteristic distance characteristic value for the distance of the investigated surface determined by this device and stores in this storage device. 30. Device according to at least one of the preceding An sayings, characterized, that this first optical device is a scanning device which scans this surface to be examined continuous 31. The device according to at least one of the preceding An sayings, characterized, that this evaluation device with these distance Characteristic values and these location characteristic values at least one determined at least one structural key figure.   32. Device according to at least one of the preceding An sayings, characterized, that this evaluation device at least one quantitative ven slope value for the slope of the structure of the surface to be examined. 33. Device according to at least one of the preceding An sayings, characterized, that this evaluation device at least one quantitative ven sharpness parameter for the sharpness of the edges of the structure ture of the surface to be examined. 34. Device according to at least one of the preceding An sayings, characterized, that at least one evaluation structural key figure from this at least one structural key figure and at least one of the characteristic optical quantities (gloss, Fog, sharpness, orange peel) will, or that for each of the particular characteristic optical parameters (gloss, fog, image sharpness, orange peel) at least one rating Structural key figure is determined. 35. Device according to at least one of the preceding An sayings, characterized, that at least one lower and / or at least one upper limit for this at least one structural key figure and / or this at least a characteristic optical one Parameter and / or this at least one evaluation Structural key figure can be specified, the lower or lower Exceeding a message on this issue- Setup or an alarm signal is issued.   36. Device according to at least one of the preceding An sayings, characterized, that at least one of these at least one limit by measuring at least one reference surface automa be determined table. 37. Device according to at least one of the preceding An sayings, characterized, that an input device is arranged, in which the User a type identifier for the surface to be measured type and that the subsequent measurements with reference to this type identifier in this memory direction are stored permanently. 38. Device according to at least one of the preceding An sayings, characterized, that an on / off switch is additionally arranged, and that the user when switched on by an acoustic and / or optical signal is asked to enter this Setup a type code for the waiter to be measured to enter the area type. 39. Device according to at least one of the preceding An sayings, characterized, that the user by entering a type change character or by pressing a type change switch this off values device switches to a type change mode, and that after entering another type identifier, the Er results of subsequent measurements with reference to this white tere type identifier in this memory device permanently be filed. 40. Device according to at least one of the preceding An sayings, characterized,  that the user after each measurement by entering a code user assessment number in this input facility this Can evaluate the measuring surface, and that this user rating number along with little at least one of these parameters and values and this little at least one evaluation structural key figure in this memory device is permanently stored, this user rating number being a subjective measure of the user for the quality of this measuring surface, and the range of values of this user rating number at least two different values, the "good" and correspond to "bad". 41. Device according to at least one of the preceding An sayings, characterized, that this evaluation device at least part of this user assessment stored in this storage device numbers and associated parameters and values for au automatic determination of at least one of these at least a limit value is used for this type identifier. 42. Device according to at least one of the preceding An sayings, characterized, that this device relative to the measuring surface in a we is considerably displaceable in the same direction, and that a distance measuring device is provided, which quantify this relative shift, and that a storage device is also provided, in which cher the along predetermined measuring points on the surface measured structural parameters and / or optical parameters can be saved. 43. Device according to at least one of the preceding An sayings, characterized,  that at least one measuring wheel is provided, which during the measurement is placed on the surface to be measured, and during the relative movement between the device device and the surface to be measured. 44. Device according to at least one of the preceding An sayings, characterized, that at least one of these has at least one measuring wheel an angle encoder is connected, which is an electrical Rotation angle signal, which for the from the measuring wheel angle of rotation traveled is representative. 45. Method for quantified determination of the quality of structured surfaces, in particular using a device according to at least one of the preceding claims, in which
a first optical device with a first light source is provided to direct light at a predetermined angle to a surface to be measured, and
a second optical device is provided, which we at least has a photo sensor, which is oriented at a second predetermined angle to this measuring surface to receive the light reflected from the measuring surface, said at least one photosensor outputs an electrical measurement signal which is used for the recorded light cha is characteristic, and
an evaluation device is arranged which controls the measurement sequence and which includes at least one processor device and which stores these measurement signals in a memory device, and
an output device outputs the measurement results, and this evaluation device evaluates this reflected light and derives therefrom at least one structural characteristic number which characterizes structure-related properties of the surface.