WO2010055498A1

WO2010055498A1 - Device and system for the optical diagnosis of alterations of the human body-surface

Info

Publication number: WO2010055498A1
Application number: PCT/IB2009/055121
Authority: WO
Inventors: Lajos Kemény; Rolland Gyulai; Judit LÁZÁRNÉ OLÁH; József DOMBI
Original assignee: Dopti Kft
Priority date: 2008-11-17
Filing date: 2009-11-17
Publication date: 2010-05-20
Also published as: HU231396B1; HU0800684D0; HUP0800684A2

Abstract

A device for the diagnosis of alterations of the human body-surface, primarily the skin, comprising an optical image recording device and a data storage and/or data processing device connected to the optical image recording device, which is a digital imaging sensor associated with at least one light source, the imaging sensor is connected to an image recording device, and the latter, in turn, is connected to a data storage and/or data processing device.

Description

Title of Invention: DEVICE AND SYSTEM FOR THE OPTICAL DIAGNOSIS OF ALTERATIONS OF THE HUMAN BODY- SURFACE

Technical Field

[1] The present invention relates to a device for the diagnosis of alterations of the human body-surface, primarily the skin, comprising an optical image recording device and a data storage and/or data processing device connected to the optical image recording device. Background Art

[2] There has been a long standing need in the area of health care and, especially, in dermatology, for the simple, almost first-glance detection of alterations of the human skin, their extent and pace. Apart from the basic method, i.e. the one when a doctor or inspecting person examines the condition of a designated skin surface area by viewing, by looking at it, in most cases, some device is used to accomplish the said objective, which facilitates diagnosis with the naked eye. It is a common feature of such devices that they are hand-held; they most often comprise a light source and an optical element, a lens, of some sort; and in most cases they are equipped with batteries to operate the light source. As for the use of such devices, on approximating the skin surface under examination, the integrated light source is activated, and it illuminates the skin surface range under inspection, and the skin surface or alteration, decisively its size, colour, crenated outline etc. is examined through the magnifying optical lens of the device. As will be obvious for a person skilled in the art, the said devices do nothing but help viewing with the naked eye, and every other diagnostic task is relegated to the person doing the inspection. According to a further characteristic of the said devices, they are suitable for both dry and wet skin examination, and the lens is to be focused on the skin surface area under examination by the user. In many devices, the illumination is adjustable; it may be polarised or non-polarised light.

[3] That is, a dermatoscope is a non-invasive diagnostic instrument which can visually detect or show the potentially dangerous, suspicious patterns of the skin, as well as structures under the skin that would mostly go unnoticed by the inexperienced eye. The dermatoscope is often called a skin surface microscope, epiluminescent microscope or episcope. Some diseases are always associated with certain, identical, dermoscopic patterns, and the same patterns, if detected, can be used for diagnostic purposes.

[4] The governing principle of dermascopy is to illuminate a skin alteration and examine it under high magnification, to detect even minor characteristics. Light directed at the skin is reflected, refracted, absorbed. This phenomenon is influenced among other things by the physical characteristics of the skin. Figure 1 also shows the principle of dermascopy. As can be seen, through a window contacting the skin via the contact liquid, light emitted by the integrated light sources of the device enters under the epidermis of the skin where it is refracted, and then it traverses the macule to arrive to the lens through which the observer experiences the skin alteration as a distinct pattern. The majority of light falling on dry, scaly, peeling skin is reflected, but smooth, oily skin allows a major part of light directed at it to penetrate it and to reach the deeper sub-epidermic layer. This is the principle applied to enhance the visibility of under- surface skin structures by spreading various contact or mediating liquids onto the examined skin surface area, to enhance the transparency of the skin thereby. Such contact liquids may be oils (e.g. mineral oils, olive oil, immersion oils etc.), water, antiseptic solutions and glycerine. Immersion oils are no longer used due to their harmful ingredients; water and antiseptic solutions evaporate quickly and are therefore less advantageous than the oils. Very often, liquid paraffin is used, which is cheap and safe, easy to procure and provides for good results. The refraction coefficient of glass, 1.52, is similar to that of the human skin, which is 1.55, hence if a glass plate is pressed onto a skin area covered with oil, that will further enhance the transillumination of the skin area under study.

[5] The main components of the dermatoscope are as follows: every dermatoscope comprises an achromatic lens which mostly provide ten-fold magnification, although special lenses offering higher magnification are also used. The devices typically have integrated illumination. The illumination may be provided by a halogen light source, placed at an angle of approximately 20° in the hand-held device. The colour of the skin spots is altered by the yellow light component of the halogen lamp. Lately, incandescent lamps have been driven out of use to a growing extend by light-emitting diodes (LEDs) which can produce high-intensity white light and consume 80% less energy than halogen lamps. The illumination can be altered by switching groups of LED lamps on and off. From among the LEDs, not only LEDs emitting white light are used: many devices use several LEDs or LED groups of various colours to make the skin more visible, since the depth of the entry of light in the skin is proportional with the wavelength of the light.

[6] Illumination makes it necessary for the devices to comprise a kind of source of energy; in hand-held devices, these are mostly one-way or rechargeable batteries and, in particular, mostly Ni-MH (Nickel- Metal Hybrid) or lithium accumulators. There are only a few dermatoscopes with the typical feature of an integrated photography system, which can be such as the already mentioned traditional camera suitable for receiving an adapter, or a digital camera or integrated camera of some sort and in such case of course also the software associated with the camera, governing its operation, that will provide for the storage, retrieval and occasionally display of the images.

[7] 3Gen LLC, USA manufactures and distributes hand-held devices belonging to the category outlined above under the product range name of 'Dermlight'. It is a common feature of the said devices that they are designed like cameras, that is, they have a body which can be hand-held, and the lens is built into what is basically a rectangular housing, so that, through the lens of the device, the user of the device looks directly at the skin surface.

[8] It is easy to understand from the above that the known devices provide for on-site, real-time viewing and diagnosis, that is, they are decisively used by professionals who will draw conclusions as regards the skin surface area of the patient which they actually see themselves. Nowadays, however, there has been a rocketing rise in the demand for some health examinations and checks, basically the ones requiring no expertise, to be made by the patients themselves, expediently at home, and this demand rhymes with the cost-saving efforts experienced in health care. Obviously, an examination which can be made at home by anyone will impose smaller or no burden on the health care budget, and in many cases, it will produce sufficiently detailed and reliable results for the outcome of the check to be remotely examined by an expert who can, if necessary, take, if need be, the necessary measures to treat/cure the patient.

[9] The exponential increase of the pace of information technological development and the spread and rising degree of acceptance of the Internet in recent years have contributed to the fact that more and more areas apply procedures composed of or assembled from several operations separated from one another in space and time. Tele- diagnosis has been used with success also in other branches of health care. Therefore, in the designated area, the demand has emerged to make also dermatological examinations suitable for the reliable and reproducible collection and transmission of examination results, data and related information to the appropriate evaluation site.

[10] It seems self-evident in the area of dermatology that, if the result of the examinations, that is, the picture seen of the skin, can be recorded in some way, then this recorded image can be delivered, together with the accompanying information chosen at one's discretion, to the evaluation site.

[11] One obvious solution to meet the above demand is to take a picture of the skin segment under study, and to forward the photo for evaluation. The shortcoming of this solution is that, to take a usable picture, of adequate quality, requires an adequate camera (with macro function) and adequate illumination. The camera problem is the easier of the two to solve, but the general experience is that the persons taking the shots often choose the wrong illumination setting: either the intensity or the direction of the light is inappropriate, and that may eventually make the use of the pictures taken dubious.

[12] This problem is experienced with analogue as well as digital cameras.

[13] Already mentioned 3Gen LLC realised the above and designed the members of the already mentioned Dermlight dermoscope product family so as to make them suitable for being fit as adapter in front of the camera lens. One drawback of this solution is that an appropriate camera, i.e. one suitable for receiving some kind of adapter means is needed. A further problem is that the adapter means affects the optical signal path, that is, the light intensity, sharpness of the picture can be influenced in function of the camera, depending on the degree of magnification and the cleanness of the lens of the device fitted as adapter, on whether illumination integrated in the device was applied during the shooting - by the way, this is usually a rather cumbersome process - and if so, whether that illumination did or did not produce excessive luminous intensity in the camera etc. The bulky and cumbersome shape of the combined device could also be seen as a drawback. Disclosure of Invention Technical Problem

[14] The objective of the invention is to develop a hand-held device that is easy and cheap to manufacture; suitable for online as well as off line examination; the use and handling of which demands no expertise; and which can record and forward the pictures taken of the skin surface areas viewed with the device in adequate quality, suitable for further processing, to the central or shared processing section of the system including the device itself. Solution to Problem

[15] Said objective has been realised by a device for the diagnosis of alterations of the human body-surface, primarily the skin, comprising an optical image recording device and a data storage and/or data processing device connected to said optical image recording device. According to the invention the optical image recording device is a digital imaging sensor, associated with at least one light source; the imaging sensor is connected to an image recording device; and the image-recording device in turn is connected to the data storage and/or data processing device.

[16] Preferred embodiments of the device according to the invention are disclosed in dependent claims 2 to 20.

[17] Furthermore, said objective has been realised by a system suitable for the optical diagnosis of alterations of the human body-surface which comprises a device to detect the alteration and, furthermore, a central data storage and processing unit. According to the invention, the system comprises at least one device according to the present invention; the central data storage and data processing system is designed as at least one computing device comprising also a processor, provided with a storage device containing a database including predefined or selectable pieces of information in an indexed way and, furthermore, a unit which communicates with one or several devices. [18] Preferred embodiments of the system according to the present invention are disclosed in dependent claims 22 to 26.

Advantageous Effects of Invention

[19] Thanks to the proposed system, it is possible to associate with the images made by the device and to process parameters consciously selected in advance, which provides for efficient diagnosis and evaluation in terms of the time, work and costs involved.

Brief Description of Drawings [20] The invention will now be described in more detail with reference to the attached drawings which show an exemplary embodiment of the device according to the invention, whereas [21] Figure 1 is the schematic view of the longitudinal section of an embodiment of the device according to the invention, [22] Figure 2 is the schematic view of a possible electronic control system of the device according to the invention having the structure shown in Figure 1, [23] Figure 3 is the schematic view of the longitudinal section of a further embodiment of the device according to the invention, [24] Figure 4 is the schematic view of a possible electronic control system of the device according to the invention having the structure shown in Figure 3,

[25] Figure 5 is the schematic cross-section of a possible embodiment of the device,

[26] Figure 6 is the bottom view of the device according to Figure 4,

[27] Figure 7 is the front view of the device according to Figure 4, and

[28] Figure 8 is a principal scheme of imaging of the device according to Figure 4.

Best Mode for Carrying out the Invention [29] Main specifications to be considered of a preferred embodiment of the device according to the invention are: [30] 1) Ensuring wireless operation.

[31] 2) Ensuring continuous operation for at least 1 hour (without recharging or replacing the battery); this depends on the battery used. [32] 3) Replaceable, standard batteries.

[33] 4) Simple, fast handling.

[34] 5) Small size.

[35] 6) Low cost.

[36] 7) Image resolution of at least 640*480 pixels.

[37] 8) Distinctible RGB and/or infrared images. [38] 9) Ensuring continuous video operating mode for adequate positioning.

[39] 10) Use of standard formats and interfaces to facilitate the configuration of PC, PDA platforms.

[40] Given the requirement of the simultaneous fulfilment of Criteria 1), 9) and 4), the use of Bluetooth-based wireless connections seems inadequate due to their small bandwidth. Instead, the 802.11a/g (WIFI) technology offering substantially larger bandwidth should be chosen.

[41] On basis of Criteria 2)and 3) - considering an operating current drain of 1 A of the device, - at least standard-size 'AA' batteries 9 shall be used.

[42] Criteria 6), 7) and 9) are met easiest with a standard Web camera 12 (see Fig. 5) well known in the art. Considering also the wireless mode of operation as specified in Criterion 1), it is recommended to integrate a wireless or, as is commonly known, 'network' camera 12. Since large numbers of devices of this type are operated in IP- network-based surveillance systems, their component kits are elaborate, easy to access and standardised, and hence they satisfy Criterion 10) as well.

[43] The simplest way to satisfy Criterion 8) is to have several subsequent shooting sequences with illumination at different wavelengths. If Criterion 9) (continuous video operation mode) is met, that implies no substantial loss of exposition time: calculated with 3 or 4 shots by colours and 4 different illuminations, respectively, and an image frame rate of 30 fps, the exposition sequence requires no more than approximately half a second. It is a further advantage of the proposed sequential illumination method that it makes it possible to acquire simple infrared spectrum images.

[44] In the planning phase, from among the CCD and CMOS semiconductor- technology-based camera modules, the choice fell on CMOS technology due to its lower energy demand. It is preferred to integrate a complete camera module 12, capable also of independent operation as a camera, into the pilot device. Considering the connection capabilities of the camera with a host computer, the camera 12 of the pilot device can be a WEB camera with USB interface, or a wired or wireless LAN camera with antenna 10 (See Figs 5 to 7). For example, the following cameras are feasible options for this purpose:

[45] wireless LAN camera of the type 'AXIS 207W with a resolution of 640*480 pixels,

[46] wireless LAN camera of the type 'AXIS 207 W with a resolution of 1280x1024 pixels,

[47] USB WEB camera of the type 'TARGA WC2130' with a resolution of 1280x1024 pixels.

[48] Design of the tube-lens-camera geometry and illumination adjusted to the envisaged object surface area

[49] Determination of the suitable object-lens distance and of the focal length of the lens [50] The surface from which a clear image is received at a specific lens position is a spherical rather than plane surface. Owing to the relatively small object-to-lens distance (in case of the envisaged 2 cm-diameter examination area), this produces significant deviation in case of a plane object surface covered by a glass plate in terms of sharpness between the edge and the centre of the image, respectively. That is, either the centre of the image is clear and its edges are fuzzy, or the edge is clear and the centre is fuzzy. (The optimum is an intermediate lens-to-object distance, where the image is clear in a ring-shaped area but, considering the entire image, there is no significant deviation from the ideal distance).

[51] A known solution to the problem is to increase the lens-to-object distance parallel with the increase of the focal length of the lens, in which case the size of the area under study will remain by and large unchanged.

[52] Exemplary parameters, defined experimentally, in view of the scanning surface sizes of the cameras to be built in, for CMOS cameras of resolution 640x480 pixels or 1280x1024 pixels: lens-to-object distance (tube length): 70 mm, focal length of the lens: 8 mm. At such parameter values, the useful image diameter is around 20-30 mm. The image scanning area of the camera with resolution 1280x1024 is larger, so a lens with longer focal length, of around 11 mm, can also be used with it.

[53] Determination of the tube geometry

[54] To define the geometry of the tube, the criteria of non-glossy-type surface illumination, adequate luminous intensity and homogenous illumination had to be taken into consideration in the first place. Further design criteria included a relatively small size and easy manufacturing. On the basis of these criteria, the exemplary tube shown in Figure 1 was created, in housing 1, with lens 2, LEDs used as light source 3, a reflecting surface 4, a diffuse white surface 5, and glass plate 6 in contact with the skin surface under study.

[55] Problems of non-glossy and homogenous illumination

[56] The problem of the non-glossy surface can be treated jointly with the homogeneity of the illumination if LED light sources 3 are placed at an adequate distance from the object, so that no illuminating light from the object plate should reach lens 2 directly. The tube form shown in Figure 1 is the result of lengthy experimentation. The adequate object illumination distance and the necessary low illumination angle is provided, at the small size required, by the double reflection of the light beam/object trajectory, which increases substantially the high apparent lens 2 to light source 3 distance required for non-glossy quality as compared to the real one.

[57] Homogenous illumination is ensured by the matte white finish on second reflecting surface 5, and high luminous intensity by the mirror foil on first reflecting surface 4.

[58] In the initial experiments, the adequate luminous intensity and homogeneity of the il- lumination was a problem. Small size and strongly focused light due to LED illumination was a serious problem during the experiments. If light source 3 illuminates the object through too many reflections, then the luminous intensity is very small; if there are few reflections, then it is not homogenous enough.

[59] Selection of the illumination colours

[60] The indicative criteria of colour selection were to cover the widest possible spectrum and to observe the momentary technological limits. Based on Claridge E, Cotton S, Moncrieff M, Hall P (2006) Spectrophotometric Intracutaneous Imaging (SIAscopy): Method and clinical applications. Chapter 37 in Handbook of Non-Invasive Methods and the Skin (2nd ed). Serup J, Jemec GBE, Grove G (Eds), 315-325: CRC Press, the wavelength range of 400-1000 nm was selected for the examination.

[61] Considering the LEDs offering adequate luminous intensity and available commercially, the following devices were chosen:

[62] 1. - for infrared: IR-LED 11 of the type of 'K001886 L-53 F3BT, wavelength

940 nm;

[63] 1. - for red: LED 12 of the type of 'K001905 L-53 SRC-E', wavelength 660 nm, illuminating power: 2800 mCd;

[64] 1. - for yellow: LED of the type of 'KOO 1500 L-53 SYC, wavelength 590 nm, illuminating power: 1000 mCd;

[65] 1. - for green: LED 13 of the type of 'K000327 L-53 VGC-E', wavelength

560nm, illuminating power: 4500 mCd;

[66] 1. - for blue: LED 14 of the type of 'K001507 L-7113 PBC, illuminating power:

1600 mCd;

[67] 1. - for ultraviolet: LED of the type of 'KOOl 179 L-7113 UVC, wavelength 400 nm, illuminating power: 160 mCd.

[68] Determination of the number of LEDs

[69] The goal was to have the greatest possible luminous intensity by colour; therefore, within the limits imposed by the geometry, the maximum feasible number of LEDs, i.e. 3 by colour, 6x3, altogether 18, was built in, in the following composition: infrared - red - yellow - green - blue - ultraviolet. White illumination was realised as the adjustable combination of red/green/blue illuminations (white balance).

[70] Low luminous intensity would make the camera excessively sensitive to the penetration of external light. Where the glass does not lie on the skin surface under study with its entire surface, or if it is not sufficiently pressed onto the surface, if the external light is too strong, it may penetrate quite forcefully at the image edges and deteriorate image quality significantly.

[71] Colours of the images to be made

[72] In addition to the above homogenous colours, the white illumination option as a com- bination of adjustable proportions of the red/green/blue illuminations has also been included to facilitate search on the skin surface.

[73] Determination of the illumination work cycles

[74] The illumination work cycles, as well as the PWM (Pulse Width Modulation) luminous intensity regulation of the individual colours, white intensity and white balance included, are governed by the control circuit. Separate illuminating power regulation by colour is necessary to ensure even illumination during colour changes. Whether a video flow or separate images are recorded, if colour changes were accompanied by changes in illumination intensity, a fix shutter speed setting would result in the under- or over-exposure of the individual images, whereas an automatic shutter speed setting would cause loss of adjustment time and hence enhance significantly the time demand of recording the image sequence of an examination.

[75] Image sequences characterised by balanced luminous intensity can be acquired by the trial-based adequate choice of programme parameter values.

[76] Preparation of the control circuit

[77] Choice and dimensioning of adequate circuit types

[78] Circuit design was governed primarily by the requirements of small size and relatively low material cost of the device. The programmable micro-controller-based control circuit 15 structure met both criteria. Owing to its relatively simple operation, small size and cost and the possibility of in-circuit programming, Microchip's circuit PIC16F84A, the exemplary structure of which is shown in Figure 2, was chosen.

[79] LED circuitry

[80] The next essential circuit detail is the switching technique of the LEDs. At continuous operation, each LED device used as light source in the envisaged circuit can withstand a forward biased current of maximum 25 to 30 mA without damage (overheating). In case of switching-mode control with a fill factor of 10%, this value will be 150 mA for each device. Due to the non-linear current/illuminating power relationship characteristic of LED devices, luminous intensity provided by a drive current of a smaller effective value of 15 mA corresponds approximately that of a continuous current of 25 mA. Thus low-fill-factor switch-mode control actually results in energy saving. The drawback of this solution is that in case of a control malfunction for some reason (causing a continuous current of 150 mA), the devices become inoperative quickly and irreversibly. In a pilot device, continuous control for a current of 25 mA was built in, in the form of a current generator adjusted to the voltage/current characteristic of LEDs of different colours (or material).

[81] Choice and dimensioning of the elements of the switching circuit; design of the control circuit

[82] Since the LEDs providing for the illumination are arranged in groups of three, the current generator's current of 75 rnA must be borne permanently also by the switching devices of the LEDs. The control signal of the switching device is adjusted to the output signal level and load capacity of the microcontroller PIC. In consideration of these criteria, the choice fell for example on SGS-Thomson's ULN2804A DIL-case style transistor array.

[83] The circuit shown in Figure 2 is designed in consideration of the above criteria and the recommendations of the circuit manufacturers concerned.

[84] The operating programme

[85] The operating programme was written directly in the own assembly language of the integrated micro controller PIC16F84A. In its current state, the operating programme controls the operation of the camera in the following way:

[86] If the camera is active, white illumination is switched on (in R-G-B cyclic order), then by pressing a single (camera) button 8 (Fig. 5), the camera automatically shots recordings with white, infrared, red, yellow, green, blue and ultraviolet illumination, respectively.

[87] Preparation of a device suitable for the in-circuit programming of the integrated micro controller

[88] In a pilot device, simultaneously with the camera 12, a circuit suitable for the direct programming of the internal micro controller, without disassembly of the device, was constructed as well.

[89] In a further possible embodiment, the device according to the invention is a wireless camera 12. A wireless LAN camera 12 of type AXIS 207MW, with resolution of 1280x1024 pixels, was integrated into the device.

[90] Desisn of the tube-lens-camera seometry and illumination adjusted to the size of the envisaged object surface area

[91] In the first version of the device, the lens-to-object distance (length of the tube) was accordingly defined at 70 mm for a lens with 8 mm focal length. However, concrete clinical experience suggested that the diameter of about 35 mm of the resulting examination surface area was too big and, consequently, the focal length of the lens was changed already in the first version to 11 mm. With an unchanged (70 mm) tube, the diameter of the examination surface area was about 20 mm, which was adequate for diagnostic purposes.

[92] In a second, wireless version of the device, the original lens of 8 mm focal length was used again and the length of the tube was reduced to reduce the diameter of the surface to be examined. The length of the shorter tube was 45 mm, so, with a lens of 8 mm focal length, the diameter of the area to be studied measured on the narrower side of the image surface was 24 mm.

[93] Because of the shorter tube, the tube structure is redesigned as well. The tube geometry had to be defined in consideration primarily of the requirements of non- glossy illumination, appropriate luminous intensity and the homogeneous illumination. Further design criteria included a relatively small size and easy manufacturing.

[94] The issue of non-glossy illumination was raised again by the reduction of the length of the tube to 45 mm. Since in the shorter tube there was not enough space any more for the arrangement shown in Figure 1, the exemplary tube represented in Figure 3 was created. Instead of the bigger apparent lens-to-light source distance, glossy appearance was prevented in this case by a shading ring. In the figure, the light ray courses reflected from the glass and to be avoided by the lens are shown in arrows in dotted lines.

[95] In the first version of the device, in addition to the above homogenous colours, the white illumination option as a combination of red-green-blue illuminations of adjustable proportions (white balance) was included as well to facilitate search on the skin surface. In the subsequent version, white illumination mixed from the three basic colours was replaced by the integration of 'white colour' LEDs. The integration of white LEDs simplifies the structure of the device, but the white balance setting option is lost in this version.

[96] In the second embodiment, in consideration of the clinical experiences, images with homogenous green illumination were omitted and the green LEDs were replaced by white ones. The integrated white LEDs are e.g. of type 'K003966 L-54 PWC with an illuminating power of 1000 mCd. Exemplary composition of the LEDs is: white - infrared - red - yellow - blue - ultraviolet.

[97] The circuit represented in Figure 4 was designed in view of the above criteria and in consideration of the recommendations of the circuit manufacturers involved.

[98] At an active camera the white illumination is switched on (in R-G-B cyclic order), then by pressing a single (camera) button 8, the camera automatically shots images with white, infrared, red, yellow, green, blue and ultraviolet illumination, respectively.

[99] The operating programme was written directly in the own assembly language of the integrated microcontroller of the type ' PIC16F84A'. In its current state, the operating programme controls the operation of the camera 12 in the following way:

[100] The camera 12 is switched on and off by pressing the camera button 8 for a longer time of e.g. 5 seconds. When the camera button 8 is pressed, the indication light of the camera 12 changes to yellow and it remains on until the time needed for switch on/off is off; if the camera button 8 is pressed for a shorter time, no change occurs in the mode of operation.

[101] Upon switch-on, the camera enters standby mode. Standby mode is indicated by the red blinking light of the indication light of the camera. In standby mode, the internal wireless camera enters switch-on state. The actual state of the internal wireless camera is indicated by the LED on the left side of the device. Yellow colour indicates initialisation and the green colour indicates operational state. The device can be made operational by continuous white illumination and the continuous green check signal of the station logging into the camera, by setting the output of the wireless camera to a low level. Pressing the camera button 8 of the operational camera for a short time initiates a white - infrared - red - yellow - blue - ultraviolet illumination sequence indicated by the continuous red light of the indication light of the camera. The control signal reports the individual colour changes to the operating programme by setting the input of the wireless camera to a pulse-like low level.

[ 102] Power supply

[103] Given an opening voltage of 4 V of the UV-LEDs and the residual voltage of the switching transistors in the control circuit, a power-supply voltage of at least 5 V is required. Currently, four Ni-MH batteries of 1.2 V each are built in (due to the battery holder, however, later on it will be necessary to change over to 6 V-lithium-ion batteries 9). A possible schematic arrangement of the batteries 9 is shown in Figures 5 and 6.

Claims

[Claim 1] 1. Device for the diagnosis of alterations of the human body-surface, primarily the skin, which comprises an optical image recording device and a data storage and/or data processing device connected to the optical image recording device, whereas

- the optical image recording device is a digital imaging sensor associated with at least one light source (3),

- the imaging sensor is connected to an image recording device,

- the image recording device, in turn, is connected to a data storage and/or data processing device.

2. Device as defined in Claim 1, wherein the digital imaging sensor is a CCD image sensor.

3. Device as defined in Claim 1, wherein the digital imaging sensor is a CMOS camera (12).

4. Device as defined in Claims 2 or 3, wherein the digital imaging sensor is a sensor producing colour images.

5. Device as defined in any one of Claims 1 to 4, whereas the light source (3) comprises one or several light sources emitting light of various wavelengths.

6. Device as defined in Claim 5, whereas the light source (3) is associated with at least one colour filter.

7. Device as defined in Claim 5, whereas the light source (3) is a light emitting diode (LED).

8. Device as defined in Claim 7, whereas it comprises several light emitting diodes of different colours.

9. Device as defined in any of Claims 1 to 8, whereas the image recording device is a digital camera (12).

10. Device as defined in any of Claims 1 to 9, whereas the data storage device is a semi-conductor storage device.

11. Device as defined in Claim 10, whereas the semi-conductor storage device is a replaceable memory card.

12. Device as defined in any one of Claims 1 to 11, whereas the data storage device is connected to a programmable data processing device.

13. Device as defined in any one of Claims 1 to 12, whereas it has an interface which provides for contact with the diagnostic system.

14. Device as defined in any one of Claims 1 to 13, whereas it is designed as a battery-powered hand-held device.

15. Device as defined in Claim 14, whereas the hand-held device is arranged in a water resistant housing.

16. Device as defined in any of Claims 1 to 15, whereas the part coming in contact with the human body-surface is designed as a single use, detachable and disposable part.

17. Device as defined in Claim 16, whereas the disposable part is an optically neutral plastic foil.

18. Device as defined in Claim 13, whereas the interface is an interface according to the WI-FI standard.

19. Device as defined in Claim 13, whereas the interface is an interface according to the Bluetooth standard.

20. Device as defined in Claim 13, whereas the interface is an interface according to the USB standard.

21. A system for the optical diagnosis of alterations of the human body- surface, which comprises a device to detect the alteration, and a central data storage and processing unit, whereas

- the device is a device according to any one of Claims 1 to 20,

- the central data storage and data processing unit is designed as a computing device which comprises at least one processor, and is equipped with a chip containing a database including predefined or selectable information in an indexed way,

- the system comprises a unit which communicates with the device.

22. The system as defined in Claim 21, whereas the storage device is a semi-conductor storage device.

23. The system as defined in Claim 21, whereas the storage device is a hard disk.

24. The system as defined in any of Claims 21 to 23, whereas the computing device is a personal computer.

25. System as defined in any one of Claims 21 to 23, whereas the computing device is a computer network.

26. System as defined in any one of Claims 21 to 23, whereas the computing device is a PDA.