DESC:FIELD OF INVENTION
[001] The present invention generally relates to analyzing and validating originality / authenticity of an artwork. More specifically, the present invention relates to a spectroscopic method and apparatus configured to dating of the colour pigments that will help to determine age of the artwork, thereby validating if it is a antique work.

BACKGROUND OF THE INVENTION
[002] The examination of colors on works of art is significant in artwork protection as it prompts detailed characterisation of materials and is in this way significant for dating and verification, just as for conceivable preservation or reclamation of fine art. Accordingly, the information on the specific substance and the idea of materials on masterpieces is the basis to choose the preservation technique to be utilized. A few insightful methods for the recognizable proof of colors have been in need for a long time. Prior to the coming of present day logical examinations, understanding the materials and strategies utilized by artists depended basically on connoisseurship, an emotional evaluation dependent on workmanship authentic information. Instrumental methods for characterisation and investigation can add to more exact information on material pieces. A work of art is an exceptionally unpredictable article and to obtain applicable data about its composition, the utilization of explicit and non-destructive insightful procedures is indispensable.

[003] Raman Spectroscopy is one of the methods which have the capability to obtain such information. It is an atomic vibrational method that is situated in the scattering of a laser beam by the particle's material which is being analyzed. Due to its high explicitness and the likelihood to perform direct examination of articles, this spectroscopic method has become an incredible asset in the investigation of social legacy and has been effectively applied to the examination of shades, records and painting artworks, among others. These days, the accessibility of versatile Raman spectrometers allows the in situ investigation of items in exhibition halls, archeological locales, and so on. Raman investigation along with other spectroscopic strategies like XRF can yield a total portrayal of the material piece of an article. The explicitness of Raman spectroscopy specifically has demonstrated helpful while deciding the arrangement of both inorganic and natural pigments. Most shades are without any problem recognizable by their Raman spectra when contrasted with a reference library. Moreover, in light of the fact that the area in a Raman range is autonomous of the excitation frequency, lasers with frequencies in the near infrared district can be utilized to restrict fluorescence while forestalling harm to conceivably invaluable fine art. There are not many understudy focused, undergrad lab tests investigating the manner in which Raman spectroscopy can be utilized in the assessment of artwork.

SUMMARY OF THE INVENTION:
[004] In accordance with the above the primary objective of the present invention is to develop and describe a non-invasive method dating of the color components by examination of artwork utilizing spectroscopic technique.
[005] It is an object of the present invention to provide a technique to determine whether an artwork, such as a painting, is authentic.
[006] The method of the present invention is a spectroscopic method that enables the dating of the painting, thereby assisting in determining if the painting is authentic.
[007] In an embodiment, the said method selecting plurality of positions A, B, C, D on the painting; extracting a spectral data SDA, SDB, SDC, SDD corresponding to the positions A, B, C, D respectively, said extraction is performed by impinging a laser beam of a predetermined wavelength the positions A, B, C, D; and comparing said spectral data SDA, SDB, SDC & SDD with a historical data DH to determine the age of the painting.
[008] The laser beam is adjusted with a specific power percentage and an exposure time on each of the positions A, B, C, D. It may be noted that the power percentage and the exposure time is not the same on all the positions.
[009] The historical data DH includes any graphical data, tabular data or any other form of data available in the literature, or a public domain.
[010] The present invention also discloses apparatus for spectroscopically determining an age of a painting on a medium.
[011] The said apparatus comprises a laser source of a predefined wavelength; a first filter and a second filter; and a spectroscopic unit.
[012] The spectroscopic unit comprises a spectrometer, a magnifying lens, and an image capturing device.
[013] The method described in the present specification is non-invasive and are thus of particular use for expensive artworks and ancient relics and thus the authentication of originality of their analogues thereof.

BRIEF DESCRIPTION OF THE FIGURES
[014] Following figures illustrate the embodiments of the present invention and the examples of the working the invention.
Figure 1 illustrates Raman spectrum of unknown pigment (a) reference spectrum of Ultramarine blue (b). As both spectra have coincident Raman bands the unknown pigment is identified as Ultramarine blue.
Figure 2 illustrates it illustrates selection of appropriate points A, B, C, D on an artwork, which in this case is a Painting
Figure 3(a) illustrates the spectral data obtained at Point A.
Figure 3(b) illustrates the historical spectral reference data of red lead.
Figure 3(c) illustrates point A on the painting
Figure 4(a) illustrates the spectral data obtained at Point B.
Figure 4(b) illustrates the historical spectral reference data of barium yellow orange.
Figure 4(c) illustrates the historical spectral reference data of chrome yellow orange.
Figure 4(d) illustrates point B on the painting.
Figure 5(a) illustrates the spectral data obtained at Point C.
Figure 5(b) illustrates the spectral reference data of TiO2 white anatase
Figure 5(c) illustrates the point C on the painting
Figure 6(a) illustrates the spectral data obtained at Point D.
Figure 6(b) illustrates the historical spectral reference data which belongs to Indian yellow.
Figure 6(c) illustrates the point D on the painting.
Figure 7 illustrates an apparatus of the present invention

DETAILED DESCRIPTION OF THE INVENTION:
[015] The present invention relates to a method of dating colour pigments in an artwork.
[016] The present invention further relate to Raman data mapping with spectral libraries and identification of the age of the components with the assistance of previous colour libraries in existence.
[017] The method of the present invention is simple, cost effective, can be implemented with any oil paintings or artworks. The method of artworks authentication by the present invention could meet the demand for artworks identification and recognition.
[018] Accordingly, the present invention discloses a spectroscopic method to determine the age of the colour pigments.
[019] The method comprises steps of:
- selecting plurality of positions A, B, C, D corresponding to different colour pigments on the painting;
- extracting a spectral data SDA, SDB, SDC, SDD corresponding to the positions A, B, C, D respectively, said extraction is performed by impinging a laser beam of a predetermined wavelength on the positions A, B, C, D, wherein
- on the position A the laser is impinged for a predetermined power percentage PPA & exposure time ETA,
- on the position B the laser is impinged for a predetermined power percentage PPB & exposure time ETB,
- on the position C the laser is impinged for a predetermined power percentage PPC & exposure time ETC,
- on the position D the laser is impinged for a predetermined power percentage PPD & exposure time ETD; and
- comparing said spectral data SDA, SDB, SDC & SDD with a historical data
[020] For the purpose of impinging the laser source at point A, the power percentage PPA is adjusted to 12%. The exposure time ETA of the laser source on point A 20 seconds.
[021] On point B, the laser with the power percentage PPB 12% is impinged with the exposure time ETB of 40 seconds.
[022] On point C, the laser with the power percentage PPC 7% is impinged with the exposure time ETC of 15 seconds.
[023] On point D, the laser with the power percentage PPD 7.5% is impinged with the exposure time ETB of 15 seconds.
[024] The laser source has a predefined wavelength of 532 nm, a power grating of 1500 and magnification of 20x, for the purpose of the present invention.
[025] The described method, being spectroscopic, is non-invasive, non-destructive and cost effective.
[026] The present invention further describes an apparatus which enables implementation of the aforesaid method. The apparatus comprises of a laser source of a predefined wavelength; a first filter and a second filter; and a spectroscopic unit.
[027] The present invention will now be described in detail with reference to optional and preferred embodiments so that various aspects of the invention will be more clearly understood, however, should not be construed to limit the scope of the invention. The reference to the drawings is included in the examples given below for better understanding of the invention.
Examples:
1. Method of Raman Spectroscopy:
[028] The Raman data has been taken from the points A, B, C, D as marked in Figure 2. The marking of the said points is determined by the presence of different colours on the medium. As a source, A Green laser was used along with ND filter and EDGE (Rag) filter. The wavelength was set at 532nm. The power grating was fixed at 1500 and magnification at 20x at all places. The power percentage and exposure time was varied for each of the points of focus to get clean peaks.
[029] Typically, a wavelength of 830 nm is viable at diminishing fluorescence while advancing adequate Raman scattering power to permit spectral recognizable proof by and large, yet in circumstances where fluorescence is not an issue, 514.5 nm is likely to amplify Raman scattering proficiency, decrease absorption times, limit ingestion and reduce risk of heat damage. From these investigations, the best results for the assessment of fluorescent examples could be achieved by employing a 532 nm laser illumination for the best results.
2. Mapping Raman data with Spectral Libraries
[030] From the position A, the spectral data is extracted. The obtained spectral data is plotted in Figure 3(a). The power percentage was at 12% and exposure time was 20s.After analysis this peak can be assigned to Red Lead.
[031] From position B, the spectral data is extracted. The obtained spectral data is plotted in Figure 4(a). The power percentage was at 12% and exposure time was 40s. After analysis the peak can be assigned to a combination of saffron and Indian Yellow.
[032] From the position C, the spectral data is extracted. The obtained spectral data is plotted in Figure 5(a). The power percentage was at 7% and exposure time was 15s. After analysis the peak can be assigned to a combination of Tio2 white Anatase and saffron.
[033] From the position D, the spectral data is extracted. The obtained spectral data is plotted in Figure 6(a). The power percentage was at 7.5% and exposure time was 15s. After analysis the peaks can be assigned to Indian Yellow.
[034] The following are the estimated colours being used in the artwork and its approximate timeline when they came to use or when its use has been recorded.
[035] The Red Lead used in the position A came into use around the 1400s. The reference spectrum of the red lead is shown in Figure 3(b).
[036] The Saffron used in position B and C came into use around the late 14th century.
[037] The Indian-Yellow used in position B and D came into use around the 15th century.
[038] The TiO2 white Anatase used in Position C came into use around 1910-20.
[039] By comparing the obtained spectral data with available historical reference data, one may arrive at the conclusion if the artwork is antique, or falsely claimed as antique.
[040] Although, the examples demonstrate the method for dating of pigments in the painting on the canvas, the method may be useful for any artwork. For example, the method could be useful for verifying authenticity of a vessel having a coloured artwork, and is claimed to be the antique work. The method could also be applicable for the coloured artwork on the fabric. The applicability of the present method may be extended, with some modifications falling within the scope of the invention, to the cave painting.
[041] The method could also be used alongwith other secondary, tertiary techniques, such as automation techniques, artificial intelligence, machine learning or other techniques.
[042] Advantage:
• Raman spectroscopy is a brilliant characterisation method for inspecting cultural materials because of its capacity to break down non-destructively with little sample material planning using short estimation times.
• With the enormous number of normal and manufactured materials experienced in preservation, recognizable proof of huge example and reference datasets has required the advancement of new strategies of representation and data extraction.
,CLAIMS:
1. A spectroscopic method for determining an age of colour pigments on a medium comprises:
selecting plurality of positions A, B, C, D associated with different colour pigments;
extracting a spectral data SDA, SDB, SDC, SDD corresponding to the positions A, B, C, D respectively, said extraction is performed by impinging a laser beam of a predetermined wavelength on the positions A, B, C, D, wherein
on the position A the laser is impinged for a predetermined power percentage PPA & exposure time ETA,
on the position B the laser is impinged for a predetermined power percentage PPB & exposure time ETB,
on the position C the laser is impinged for a predetermined power percentage PPC & exposure time ETC,
on the position D the laser is impinged for a predetermined power percentage PPD & exposure time ETD;
and
comparing said spectral data SDA, SDB, SDC & SDD with a historical data DH to determine the age of the pigments.
2. The method as claimed in Claim 1, wherein the power percentage PPA is 12%.
3. The method as claimed in Claim 1, wherein the exposure time ETA is 20s.
4. The method as claimed in Claim 1, wherein a peak intensity in the spectral data SDA is associated /compared with red lead.
5. The method as claimed in Claim 1, wherein the power percentage PPB is 12%.
6. The method as claimed in Claim 1, wherein the exposure time ETB is 40s.
7. The method as claimed in Claim 1, wherein a peak intensity in the spectral data SDB is associated /compared with saffron and Indian Yellow.
8. The method as claimed in Claim 1, wherein the power percentage PPC is 7%.
9. The method as claimed in Claim 1, wherein the exposure time ETC is 15s.
10. The method as claimed in Claim 1, wherein a peak intensity in the spectral data SDC is associated /compared with a combination of TiO2 white Anatase and saffron.
11. The method as claimed in Claim 1, wherein the power percentage PPD is 7.5%.
12. The method as claimed in Claim 1, wherein the exposure time ETD is 15s.
13. The method as claimed in Claim 1, wherein a peak intensity in the spectral data SDD is associated /compared with Indian Yellow.
14. The method as claimed in Claim 1, wherein the wavelength of the laser source is 532 nm.
15. The method as claimed in Claim 1, wherein a power grating of the laser source is 1500.
16. The method as claimed in Claim 1, wherein the magnification of the laser source at 20x.
17. The method as claimed in Claim 1, wherein the medium is selected from a fabric used for canvas, a paper, a hard surface, a hard uneven surface or such.
18. An apparatus for spectroscopically determining an age of colour pigments on a medium comprises:
a laser source of a predefined wavelength;
a first filter and a second filter; and
a spectroscopic unit comprising a spectrometer, a magnifying lens, and an image capturing device.
19. The apparatus as claimed in Claim 18, wherein the wavelength of the laser source is 532 nm.
20. The apparatus as claimed in Claim 18, wherein a power grating of the laser source is 1500.
21. The apparatus as claimed in Claim 18, wherein the first filter is neutral density filter.
22. The apparatus as claimed in Claim 18, wherein the second filter is edge filter.
23. The apparatus as claimed in Claim 18, wherein the magnifying lens is of 20x capacity.
24. The apparatus as claimed in Claim 18, wherein the image capturing device is a charge coupled device.