Short Description
The Virsa™ Raman device is a portable, dispersive and autofocusing Raman system with fibre-optic coupled Raman probes (532 and 785 nm), which is suitable for both micro and macro Raman analyses. This system enables non-invasive, molecule-specific, dispersive Raman investigations and chemical imaging and is ideal for studying large or immovable objects such as paintings, murals, books and sculptures. It is also possible to analyze small samples taken from works of art using the microscope integrated in the device. Liquid samples in vials can also be analyzed.
It delivers laboratory-grade performance with high sensitivity and good spectral and spatial resolution, making it particularly suitable for examining challenging samples like paint mixtures, including those from modern and contemporary art, as well as various ageing and degradation phenomena. The system is positioned on a motorized stage that moves in x, y, z directions and therefore enables 2D/3D imaging (scanning mode). This capability is particularly useful for examining degraded objects and for understanding the distribution of compounds in complex matrices such as paintings and graffiti. The autofocus function ensures that the highest possible Raman intensity always reaches the detector, which significantly increases the detection sensitivity compared to non-autofocusing Raman devices.
Contact Person
Dr. Federica Cappa
Research Services
The Institute for Natural Sciences and Technology in the Arts (INTK) and the Core Facility "Centre for Material Sciences in Art and Conservation (ZMKK)" are central facilities of the Academy of Fine Arts Vienna for the natural scientific (material) analysis of works of art. The facilities support members of the Academy of Fine Arts Vienna or other research institutions, museums, libraries, archives, etc. in the realisation of joint projects within the framework of research funding or contract research and also offers services (third-party funding) for external parties.
The focus is on scientific material analyses of artworks and archive materials using FTIR, (FT & dispersive) Raman, XRF, UV-Vis, HSI, RSI, ESEM (EDX), Py-GC/MS, digital X-ray radiography and photo documentation (Vis, UV, IR, IRR), microscopy, chambers for accelerated ageing of samples.
Special services provided by the Virsa™ Raman system from Renishaw, specifically applied to the analysis of art objects:
• In-situ Analysis, non-destructive & non-invasive: detailed study of art objects without causing any damage, preserving the integrity of valuable and delicate works.
• Micro and Macro Raman Spectroscopy: Capable of analyzing both minute details and samples together with larger areas, the system can be used for intricate studies on various scales, from tiny paint chips to full-sized artworks.
• Fiber-Optic-Coupled Probes: The use of fiber-optic-coupled probes enables flexible and remote analysis, which is particularly beneficial for examining large or immovable objects like murals and sculptures.
• High Spectral and Spatial Resolution: The system offers exceptional spectral and spatial resolution, crucial for distinguishing between similar pigments and identifying detailed chemical compositions in mixed media.
• Non-Invasive Imaging: Using Raman imaging with LiveTrack autofocus function, the system can visualize the distribution of pigments and other materials across an artwork, aiding in the understanding of artistic techniques and material composition.
• Wide Spectral Range: The system covers a broad spectral range, allowing the detection of a wide variety of materials, including both organic and inorganic components commonly found in art.
• Versatility in Sample Types: It is capable of analyzing different forms of art objects, including paintings, manuscripts, graphics, drawings, sculptures, and even liquid samples, making it a versatile tool in art conservation and research.
Methods & Expertise for Research Infrastructure
The portable,dispersive Virsa Raman system offers in-situ non-destructive and non-invasive Micro-Raman analysis and chemical imaging (2D/3D), utilizing lasers with wavelengths of 532 nm and 785 nm and CCD camera (-70 °C). It is capable of characterizing pigments, inks, and materials in various works of art, including paintings, manuscripts, graphics, drawings, and sculptures. The Raman spectral range extends from 50 cm⁻¹ to 4000 cm⁻¹ with a 532 nm laser, and from 50 cm⁻¹ to 3200 cm⁻¹ with a 785 nm laser. The system provides a spectral resolution of less than 2.5 cm⁻¹, ensuring precise and detailed analysis. LiveTrack autofocus function ensures higher Raman intensity counts on detector during analysis, especially for rough and textured surfaces, compared to the Raman systems without autofocus.