Physics:Intelligent laser speckle classification

From HandWiki
An ILSC scan in progress

Intelligent laser speckle classification, or ILSC, is a scanning method used to discriminate between various micro-textural structures, such as the cellular components in human skin.[1] or discriminates sub-surface characteristics of any material (e.g. industrial, pharmaceutical, etc.)

Basic concept

An ILSC scanner is composed mainly of two instruments: A laser and a modified CCD camera.

Diagram of an ILSC scan

Light from the laser interacts uniquely with various micro-textural structures, creating a specific laser speckle effect (or signature). This signature can then be read by the incorporated camera, which utilizes Bayesian inference and inbuilt libraries of micro-textures to create a "laser speckle image" of the target.[2] Since the method is comparative, it may also be used to differentiate very small changes in micro-structural objects, for example, a change in cell size. This ability to generate "comparative" laser speckle images is again due to the interactions between the laser and the cellular objects.[3]

Applications

The concept has been found to be very effective in analyzing human skin for issues caused by ageing, especially in the lower layers of the epidermis, such as the basal layer, and has also been found to be less invasive than other methods, such as confocal microscopy.[4] The potential application areas of ILSC are as follows :

- Skin analysis: it is possible to make an automated parametric discrimination between the two different conditions of skin (e.g. normal or effected by a disease)that are invisible to human eye. This would be particularly very useful for early diagnosis of the systemic diseases where the skin does not yet exhibits their visual effects by the surface changes [3]

- Pharmaceutical inspection :ILSC is also used for pharmaceutical product inspection as the laser light (with an ideal wavelength) can penetrate into the pharmaceutical (tablet) subsurface and scatters back by conveying the subsurface material characteristics to be identified and analysed by ILSC technique [5]

- Industrial material identification : Depending on laser-material surface interaction, ILSC can identify and discriminate the different materials that are used in industrial production areas (e.g. metal, wood, plastic, etc.)[6] to make the production process in fully automated form by eliminating the most of environmental undesired lightening effects.

References

  1. "Noninvasive Imaging Method Promising for Skin Assessment". Photonics. http://www.photonics.com/Article.aspx?AID=56111. Retrieved 13 March 2015. 
  2. "Laser Doppler, speckle and related techniques for blood perfusion mapping and imaging". Kingston University. http://home.lu.lv/~ozoma/Ma%ECistri-2013/Diagnostika_un_terapija/terap/Asins-pluusmas-meeriisanai-dazi-info/PM_R35.pdf. Retrieved 13 March 2015. [yes|permanent dead link|dead link}}]
  3. Orun, A.B, E. Goodyer, H.Seker, G. Smith, V.Uslan And D. Chauhan, "Optimized parametric skin modelling for diagnosis of skin abnormalities by combining light back-scatter and laser speckle imaging", Skin Research and Technology, 2014; 1-13. doi:10.1111/srt.12142
  4. Orun, Ahmet. "An improvement of skin aging assessment by non-invasive laser speckle effect: A comparative texture analysis". De Montfort University. http://www.tech.dmu.ac.uk/~eg/ref/IEEE_BHI2014_Orun_Seker_203.pdf. Retrieved 13 March 2015. 
  5. 5. Orun, A. and G.Smith, "Micro-Structural Analysis of Tablet Surface Layers by Intelligent Laser Speckle Classification (ILSC) Technique: an Application in the Study of both Surface Defects and Subsurface Granule Structures",Journal of Pharmaceutical Innovation, (2017)DOI 10.1007/s12247-017-9290-0
  6. 6. Orun, A. and A. Alkis, "Material identification by surface reflection analysis in combination with bundle adjustment technique", Pattern Recognition Letters,24(2003)