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A hard X-ray engineering applications beamline (BL-02) was commissioned recently and started operation in March 2019 at the Indian synchrotron source, Indus-2. This bending-magnet-based beamline is capable of operating in various beam modes, viz. white, pink and monochromatic beam. The beamline utilizes the X-ray diffraction technique in energy-dispersive and angle-dispersive modes to carry out experiments mainly focused on engineering problems, viz. stress measurement, texture measurement and determination of elastic constants in a variety of bulk as well as thin-film samples. An open-cradle six-circle diffractometer with ∼12 kg load capacity allows accommodation of a wide variety of engineering samples and qualifies the beamline as a unique facility at Indus-2. The high-resolution mode of this beamline is suitably designed so as to carry out line profile analysis for characterization of micro- and nano-structures. In the present article the beamline is described starting from the beamline design, layout, optics involved, various operational modes and experimental stations. Experiments executed to validate the beamline design parameters and to demonstrate the capabilities of the beamline are also described. The future facilities to be incorporated to enhance the capabilities of the beamline are also discussed.

Room-temperature synchrotron X-ray diffraction and subsequent detailed line profile analysis of Fe powder were performed for microstructural characterization. The peak shapes of the diffraction pattern of Fe were found to be super-Lorentzian in nature and the peak widths were anisotropically broadened. These peak profile features of the diffraction pattern are related to the microstructural parameters of the material. In order to elucidate these features of the diffraction pattern, detailed line (peak) profile analyses were performed using the Rietveld method, modified Williamson–Hall plots and whole powder pattern modelling (WPPM), and related microstructural parameters were determined. Profile fitting using the Rietveld and WPPM methods with a single microstructural (unimodal) model shows systematic deviation from the experimentally observed diffraction pattern. On the basis of Rietveld analysis and microstructural modelling it is revealed that the microstructure of Fe consists of two components (bimodal profile). The microstructural parameters of crystallite/domain size distribution, dislocation density, nature of dislocations and phase fraction were evaluated for both components. The results obtained using different methods are compared, and it is shown that diffraction peak profile analysis is capable of modelling such inhomogeneous bimodal microstructures.

The interface at NiO and GaAs heterojunction is found to have claudetite phase of As2O3 with monoclinic structure, which increases with oxygen (O2) partial pressure. It is determined that rough interface, caused by recrystallization of GaAs surface along [111] direction, is not the main governing factor for the observed change in growth direction for NiO epitaxial layer from [111] to [001] direction with increase in O2 partial pressure. The out-of-plane and in-plane epitaxial relationships of [111] oriented NiO layer with respect to substrate are [111]NiO || [001]GaAs, [-1-12]NiO || [-1-10]GaAs and [-110]NiO || [-110]GaAs. The interfacial structure of NiO/GaAs heterojunction thus determined can have implications into the characteristics of optoelectronic devices based on this heterojunction.

In the last few decades there has been a remarkable growth in the development of optical spectroscopic techniques for in situ, sensitive, minimally invasive diagnosis. In this article we provide an overview of the field and highlight some representative applications. Special emphasis has been placed on the use of optical spectroscopic techniques for non-invasive diagnosis of cancer where a significant amount of work has been carried out in the country.

Photonic nanojets (PNJs) owing to their sub-wavelength near-field features have found many interesting applications like nanoscopy, nano photolithography, high density optical storage, enhancement of Raman signal and single molecule spectroscopy etc. More recently, the focus of research has been on tailoring of PNJs either for better confinement and thus higher peak intensity or for elongation of nanojet for high resolution far field applications. In this paper, we show that crescent-shape refractive index profile (CSRP) of microspheres can be used to generate highly confined PNJ. By optimizing the refractive index of different layers in CSRP microsphere, we show a free space confinement down to ∼ λ ∕ 4 . 5 (FWHM ∼ 110 nm for excitation with 500 nm wavelength). Further, it was observed that the optical properties of substrates also modulate the PNJ characteristics and lead to a further improvement in the transverse confinement to ∼ λ ∕ 6 . 7 .

Synchrotron radiation induced carbon contaminations on optical elements is a major concern for a beamline designer. Growth mechanism of carbon deposition is not well understood. Structural characterization of radiation (3.5–11.8 eV) induced contamination layer on LiF window is carried out by soft x-ray reflectivity (SXR) and grazing incidence x-ray diffraction (GIXRD) techniques. Diffraction peaks at 2θ = 28.3° (002) shows a graphitic structures and peak at 75.3° (220) show a mixed phase (carbonado) of carbon. Out-of-plane cluster/grain sizes ∼6.05 nm and ∼2.45 nm are measured respectively for crystalline graphite and carbonado phase of carbon by Debye Scherrer equation. For elemental analysis x-ray photoelectron spectroscopy (XPS) and Raman spectroscopy techniques are used. In Raman spectroscopy measurements the crystalline graphite G band (1556 cm −1 ) and disordered graphite D bands (1350 cm −1 ) are observed. In-plane cluster size∼ 9.62 nm was calculated by empirical relation using I D and I G ratio of Raman peaks. XPS peak at 291 eV indicates that most of the carbon is in the form of carbonate (ROCOOR’) that is polymerizing in form of rings/chains and converted into polymer like (PLCH) and graphitic like hydrogenated (GLCH) carbon due to continuous exposure by radiation. Contamination layer properties also compared with commercial graphitic structure.

Near-stoichiometric LiNbO 3 (SLN) single crystals were grown/prepared by top seeded solution growth/vapor transport equilibration (VTE) technique, and investigated for stoichiometry, disorder and structural defects. The optical absorption and Raman line-width studies revealed higher stoichiometry (i.e., higher Li/Nb) for SLN prepared by vapor transport equilibration (SLN_V) technique in comparison to SLN grown from K 2 O flux (SLN_K) and Li-rich melt (SLN_L). The nearly symmetric single diffraction curve (DC), though broad, as observed for SLN_L specimen in high resolution X-rays diffraction (HRXRD) analysis depicted lesser low angle grain boundaries. On the other hand, relatively sharp DC with lowest full-width at half-maximum (FWHM ∼45 arc-sec) in HRXRD and lesser Urbach energy (∼80 meV) in the absorption spectra for SLN_V crystal revealed less structural defects with respect to other SLN crystals. The higher FWHM of DCs in HRXRD for SLN_L and SLN_K is attributed to growth related imperfections usually observed in solution growth. Though, VTE process results in SLN crystals with better stoichiometry and lesser structural defects but the limitation being that samples up to ∼1 mm thickness can be prepared with this technique. For bulk SLN, growth from K 2 O flux resulted in better stoichiometry whereas Li-rich flux resulted in better structural quality. The absorption spectra of the grown SLN crystals depicted oxygen vacancy induced electronic defects (Nb 4+ , polarons), which was further authenticated by X-ray absorption near-edge structure (XANES) analysis at Nb K edge revealing lesser Nb 4+ defects in SLN with respect to congruent lithium niobate (CLN) crystal.

We report results of our studies on cellular uptake and phototoxicity of free chlorin p 6 (Cp 6) and Cp 6 bound to amine-modified silica nanoparticles (Cp 6-SiNP) in colon (Colo-205) and oral cancer (Nt8e) cell lines. Fluorescence spectroscopy-based measurement of cellular uptake showed no significant difference in the amount of free Cp 6 and Cp 6-SiNP localized in cells. Measurements on phototoxicity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that the Cp 6-SiNP was more effective as compared with free Cp 6. Fluorescence-correlation spectroscopy performed on the free drug and drug-SiNP complex in serum media confirmed that the drug remains preferentially bound to SiNP. The rate of photobleaching was much lower in case of Cp 6-SiNP complex as compared with the free drug in serum media. These results suggest that the observed increase in photodynamic activity of Cp 6-SiNP complex may arise because of an increase in the photostability of Cp 6 when bound to SiNP.

In this paper we present the results of Mueller matrix measurements on depolarization characteristics of non-spherical gold nanoparticles (rods, tetra-pods, flowers and stars). The measurements show that for all the particle shapes investigated, the depolarization for circularly polarized light is larger than that for linearly polarized light by about a factor of two. Further, depolarization is largest for the rod shaped particles. The wavelength dependence of the depolarization characteristics of the particles was also investigated and the results are consistent with the calculated wavelength dependence of retardance and diattenuation properties of these nanoparticles using discrete dipole approximation.

A minimum of 16 measurements involving both linear and circularly polarized light are required to determine the Mueller matrix of a sample which completely describes the polarization properties of the sample. In contrast a 3×3 partial Mueller matrix, devoid of last row and column of conventional Mueller matrix, can be obtained by using nine linear polarization measurements. Further, with only linear polarization measurements the limitation on spectral coverage imposed by quarter wave plates required for circular polarization measurements is avoided. However, a drawback of this approach is that the data analysis tools developed for 4×4 Mueller matrix cannot be applied in this case. To address this issue we show that for non-depolarizing media the various symmetry constraints on Muller matrix elements can be used to obtain the 4×4 Mueller matrix from the measured 3×3 Mueller matrix. This method should prove particularly useful for measurement of Mueller matrix in the spectral region for which retarders are either not readily available or inconvenient to use.

We report the results of a study carried out to investigate the potential of optical techniques such as optical coherence tomography, Mueller matrix spectroscopy, and cross-polarization imaging for noninvasive monitoring of the ionizing radiation exposure-induced alterations in cutaneous tissue of mice. Radiation dose-dependent changes were observed in tissue microvasculature and tissue optical parameters like retardance and depolarization as early as 1 h post radiation exposure. Results suggest that these optical techniques may allow early detection of radiation dose-dependent alterations which could help in screening of population exposed to radiation.

We report a study on the use of polarization sensitive optical coherence tomography (PSOCT) for discriminating malignant (invasive ductal carcinoma), benign (fibroadenoma) and normal (adipocytes) breast tissue sites. The results show that while conventional OCT, that utilizes only the intensity of light back-scattered from tissue microstructures, is able to discriminate breast tissues as normal (adipocytes) and abnormal (malignant and benign) tissues, PS-OCT helps in discriminating between malignant and benign tissue sites also. The estimated values of birefringence obtained from the PSOCT imaging show that benign breast tissue samples have significantly higher birefringence as compared to the malignant tissue samples.

Energy of the indirect and direct optical bandgap of near-stoichiometric lithium niobate (nSLN) crystals is evaluated by optical absorption measurement. The value of the indirect bandgap (3.95 eV) is consistent with the earlier reports. However, the direct bandgap energy of 4.12 eV is higher than the previously reported experimental value (3.68 eV). The direct bandgap energy obtained here is closer to the recent theoretical value estimated by Thierfelder et al. [Phys. Status Solidi C 7, 362 (2010)] in comparison to the previously predicted value by Ching et al. [Phys. Rev. B 50, 1992 (1994)]. The phonons involved in the indirect allowed transitions have energies ∼85 meV (685 cm−1) and are identified as the E(TO9) and E(LO8) optical phonon modes from the Raman scattering measurement.

Mueller matrix measurements were used to characterize the polarization properties of liquid crystal-based reflective type twisted nematic (TN) special light modulator (SLM) at oblique incidence of the laser beam. The experimentally obtained Mueller matrices were used to obtain the combination of polarization optics required to optimize it for phase only modulation. The results indicate that minimum intensity modulation is obtained with the use of a polarizer followed by a quarter wave plate (QWP) in polarization state generator (PSG) arm and a QWP followed by an analyzer in polarization state analyzer arm (PSA). Polarization parameters such as retardance, rotation and depolarization were calculated from the experimentally obtained Mueller matrices using polar decomposition method at different angle of incidences of the laser beam and the results has been discussed. The similarity between retardance and depolarization curve as a function of address voltage of TNSLM indicated that depolarization is mainly associated with errors in retardance values. Further, spectral Mueller matrix measurements were used to obtain intensity modulation response in the range of wavelengths 450-700 nm for broadband applications.

Characterization of synchrotron induced contamination on optical elements and their cleaning are serious issues in beam lines. We used Raman spectroscopy for characterization of synchrotron induced contamination layer on LiF window (used in high resolution vacuum ultra violet beam line). Three peaks at 1035 cm−1 (corresponding to C-C sp3 vibrations), 1563 cm−1 and 1375 cm−1 (corresponding to G and D bands of carbon) are observed. By data fitting I(D)/I(G) ratio (0.84) and FWHM(G)=124 cm−1 was obtained. Comparison with available literature indicates that the carbon might be present in the form of rings of hydrogenated amorphous carbon a-C:H (GLHC) with atomic hydrogen concentration about 15% with both sp2 and sp3 hybridization.

Photonic nanojet (PNJ), the sub wavelength confinement of light by dielectric microspheres is finding applications in nanoscale imaging, spectroscopy and nano lithography. These applications require control over the length and lateral dimension of the nanojets. In the paper we present the results of numerical simulation to show that a core shell microspheres can be used to generate photonic nanojet with controllable length and confinement by varying the relative refractive index of the microspheres and the separation between the core and shell centers. We show that a length of up to 27λ can be achieved when the core microsphere has lower refractive index than the shell and lateral dimensions down to λ/3 with core microsphere having higher refractive index.

We discuss the enhancement of Raman signals using a photonic nanojet generated by dielectric microspheres. The highly confined field of the nanojet leads to an order of magnitude enhancement of the Raman signal from the substrate beneath. Enhancement is observed to depend strongly on the sizes of the microspheres as well as the contrast between their refractive index and that of the sample. Enhancement increases when the refractive index of the substrate increases relative to that of the microsphere, but decreases rapidly as the two become equivalent.

Acute and transient psychotic disorder has been accepted as a distinct diagnostic entity in the ICD-10. However, there are few studies delineating its demographics and factors affecting its outcome. This study aimed to examine the socio-demographic profile of patients with acute and transient psychotic disorder and the variables associated with the onset of illness and their effect on illness outcome in an Indian setting.This was a retrospective study in which case notes of patients admitted from 1 January to 31 December 2012 and diagnosed with acute and transient psychotic disorder (according to the ICD-10 diagnostic criteria) were analysed. Socio-demographic variables and variables associated with the onset of illness were noted. Duration of hospital stay was used as a proxy measure for clinical outcome.A total of 185 patient records were analysed. Overall, 49% of the patients were males and 51% were females. Most of the cases (60%) were aged between 20 and 39 years. The majority was married, unemployed, educated up to middle school, living in a nuclear family, and had a rural background. Age (p = 0.05) and marital status (p = 0.03) significantly affected the outcome. Overall, 46% of the patients had stress as a precipitating factor, 27% reported substance use, and 23% had a family history of psychiatric illness prior to the onset of their illness. The onset of illness was from May to October in 54% of the patients, with the duration of untreated illness ranging from 7 to 15 days in 38% of the patients. The clinical outcome was significantly affected by duration of untreated illness (p = 0.05).Acute and transient psychotic disorders show slight female preponderance and occur in early adulthood. There is no precipitating stress in most cases and shorter duration of untreated illness predicts favourable clinical outcome.

Burnout is an increasing problem among the medical fraternity, especially resident doctors. We assessed the relationship between burnout, emotional intelligence and perceived stress in an attempt to explore a probable solution.Residents in the departments of medicine (n=29) and surgery (n=27) were assessed with a specially designed proforma consisting of participant's profile sheet, Shirom-Melamed Burnout Measure (SMBM), Trait Emotional Intelligence Questionnaire and Perceived Stress Scale (PSS). Correlation and mediational analysis were used to analyse the data.The findings showed a positive correlation of burnout with perceived stress and a negative correlation with trait emotional intelligence (EI). Perceived stress also showed a negative correlation with trait EI. Mediation analysis showed that perceived stress mediates the effect of trait EI on burnout.Enhancing EI through training may be an important intervention for targeting burnout.

We report results of studies on the effect of different shapes and sizes of gold nanoparticles (GNPs) on the depolarization characteristics of Intralipid tissue phantoms. For a given extinction coefficient, the absorption characteristics of the GNPs contributed more to the depolarization of the turbid medium, and the contribution of scattering was significant only for the larger-sized particles. For rod-shaped GNPs, their depolarization plays an important role in the low scattering regime in which the depolarization properties of the nanoparticles (NPs) dominate in the turbid medium even if the contribution of the scattering from the NPs is about an order of magnitude less. For highly scattering samples, GNP absorption significantly modulates the depolarization spectra of the turbid medium.

We report a scheme for polarization sensitive near field imaging of nanostructured samples by making use of broadband polarized near field illumination and detection of polarization states of scattered light by a spectrally encoded analyzer. The analyzer comprising a combination of polarizer, a multi-order waveplate and a broadband quarter waveplate allows analysis of the spectrally encoded polarization states of scattered light for characterization of the polarization properties of nano structures from a single image scan. The scheme was validated by measuring the near field polarization parameters of silver nanowires. The approach allows simultaneous measurement of polarization characteristics as well as spectral features of the nano materials.

To evaluate the status of schizotypy, neurological soft signs, and cognitive functions as vulnerability markers for schizophrenia and to investigate the potential value of their combination for early identification of people at high risk for schizophrenia.A cross-sectional study was conducted. Subjects were drawn from first-degree relatives of inpatients and outpatients with schizophrenia (n = 50). Controls (n = 30) were recruited by word-of-mouth from hospital staff and attendants of hospitalised patients. Subjects who met inclusion criteria on screening were subjected to selected measures for assessment, including Schizotypal Personality Questionnaire-Brief Version, the Cambridge Neurological Inventory, digit span test, paired associate learning test, and visuospatial working memory matrix. Statistical analysis was completed using the independent t test and significance (p value), as well as calculation of effect size (Cohen's d). Discriminant function analysis was used to determine the effect of combining assessment measures.First-degree relatives showed higher schizotypy scores (Cohen's d = 0.88) and neurological soft signs (Cohen's d = 1.55). They scored significantly worse on all neurocognitive measures (Cohen's d = -1.27). Discriminant function analysis showed that Schizotypal Personality Questionnaire-Brief Version, neurological soft signs, and total cognitive index (the sum of weighted scores on individual cognitive scales) in combination better discriminated between the first-degree relative and control groups (Wilks' λ = 0.54).Use of multiple vulnerability markers could enhance the specificity of measures used to determine risk for schizophrenia.

To assess and compare the quality of life and disability in patients with schizophrenia and obsessive compulsive disorder.A cross-sectional study was carried out in the outpatient psychiatry clinics at Jaipur of India. Fifty patients with obsessive compulsive disorder and 47 with schizophrenia (diagnosed as per criteria of the 10th revision of the International Classification of Diseases), and with a minimum duration of 2 years on maintenance treatments, were evaluated. Evaluation was based on the World Health Organization Quality of Life Instrument, the Global Assessment of Functioning scale, and the Indian Disability Evaluation Assessment Scale. The collected data were analysed using descriptive and inferential statistics.Regarding quality of life domains, there was no statistically significant difference between the 2 groups. Obsessive compulsive disorder patients had lower scores on all domains of disability, all such differences being statistically significant.The deleterious effect of illness on quality of life and functioning occur not only in schizophrenic but also in obsessive compulsive disorder patients. Thus management should be planned with this consideration to yield better outcomes in both conditions.

Mueller matrix measurements on non-spherical nano-particles (rods, tetra-pods, flowers and stars) reveal that rods result in highest depolarization and that the depolarization is larger for circularly polarized light compared to that for linearly polarized light.

Fluorescence correlation spectroscopy study showed that apart from its surface charge, the hydrophobicity of the substrate significantly influences the diffusion of the molecules and must be taken into account for a correct interpretation of the FCS data.

Polarization parameters of diffuse backscattered light from a turbid sample are sensitive to its structural properties and can, therefore, be used to probe morphological features of tissue and, thus, monitor changes that arise due to a disease. Extraction of morphological information from measured polarization parameters, however, requires a careful understanding of the dependence of these on factors such as size, size distribution, shape, and dielectric constant of the scatterers, which are often quite involved. In particular, the presence of absorption complicates the dependence of polarization parameters on tissue morphological features. We have found that, while for medium comprising small size scatterers (Rayleigh scatterers), the depolarization shows the expected decrease with an increase in the absorption of the scattering medium, a counterintuitive behavior was observed for larger size (lambda) scatterers. Further analysis of the results suggests that the observed behavior might arise due to the relative contribution of two depolarizing processes, one resulting from a series of out-of-plane scattering and the other due to the angular variation of the state of polarization in a single scattering event.

Most early cancers arise in epithelial tissue and areassociated with alterations in both epithelial cellsand stroma [1–7]. Since collagen fibers, the mainscatterers in the stroma underlying the epithelium,are birefringent it is expected that neoplasticchanges would lead to changes in the polarizationparameters (retardance, diattenuation and depolari-zation) of the tissue. By measurement of the Muellermatrix of the tissue, and its polar decomposition[8, 9], the polarization parameters of the tissue canbe extracted and used for diagnostic applications.This approach has been investigated for the diagno-sis of oral and skin cancer [4–7]. The results of thesestudies have confirmed that the normal to malignant

For in vivo determination of optically active (chiral) substances in turbid media, like for example glucose in human tissue, the backscattering geometry is particularly convenient. However, recent polarimetric measurements performed in the backscattering geometry have shown that, in this geometry, the relatively small rotation of the polarization vector arising due to the optical activity of the medium is totally swamped by the much larger changes in the orientation angle of the polarization vector due to scattering. We show that the change in the orientation angle of the polarization vector arises due to the combined effect of linear diattenuation and linear retardance of light scattered at large angles and can be decoupled from the pure optical rotation component using polar decomposition of Mueller matrix. For this purpose, the method developed earlier for polar decomposition of Mueller matrix was extended to incorporate optical rotation in the medium. The validity of this approach for accurate determination of the degree of optical rotation using the Mueller matrix measured from the medium in both forward and backscattering geometry was tested by conducting studies on chiral turbid samples prepared using known concentration of scatterers and glucose molecules.

Polarization properties of any optical system are completely described by a sixteen-element (4 x 4) matrix called Mueller matrix, which transform the Stokes vector describing the polarization properties of incident light to the stokes vector of scattered light. Measurement of all the elements of the matrix requires a minimum of sixteen measurements involving both linear and circularly polarized light. However, for many diagnostic applications, it would be useful if all the polarization parameters of the medium (depolarization (Δ), differential attenuation of two orthogonal polarizations, that is, diattenuation (d), and differential phase retardance of two orthogonal polarizations, i.e., retardance (δ )) can be quantified with linear polarization measurements alone. In this paper we show that for a turbid medium, like biological tissue, where the depolarization of linearly polarized light arises primarily due to the randomization of the field vector's direction by multiple scattering, the polarization parameters of the medium can be obtained from the nine Mueller matrix elements involving linear polarization measurements only. Use of the approach for measurement of polarization parameters (Δ, d and δ) of normal and malignant (squamous cell carcinoma) tissues resected from human oral cavity are presented.

We report the use of sub-wavelength confinement of light using dielectric microspheres for enhancing transmission through the cantilever-based hollow probes used in a near-field scanning optical microscope. With an appropriate choice of the dielectric microsphere, an order of magnitude enhancement was achieved in transmission through the probe. In addition, transmission through such a tip was also found to be less sensitive to the axial and lateral offset between the beam waist and symmetry axis of the probe tip.

Mueller matrix measurements on turbid media can be used to quantify its polarization properties in terms of retardance, diattenuation, and depolarization. In particular, the depolarizing ability of such media, which is represented by the depolarization index, has been shown to be a useful diagnostic parameter. However, being a single valued metric, its dependence on a host of tissue optical parameters makes it difficult to interpret. In this paper, we show that a map of depolarization as a function of input polarization state parameters can be used to infer information about the size of scatterer and order of birefringent and depolarizing layers in turbid medium. The experiments carried out on different mice organ tissues indicate that the depolarization characteristics of tissue are closely represented by depolarization properties of intralipid. We also observed that these maps do not vary in the presence of absorption.

Mueller matrix measurements are most commonly performed using a set of polarization state generating (PSG) optics and an independent set of polarization state analyzing (PSA) optics. However, for polarized confocal microscopy and polarization sensitive optical coherence tomography it would be advantageous if the same set of polarization optics could be used for both PSG as well as PSA. This has not been possible because, in this configuration, a complete set of incident and analyzer states cannot be generated using polarizers and waveplates alone. In an earlier attempt to address this issue it was shown that by using two Faraday rotators, with independently variable circular retardance, in the polarization optics, complete Mueller matrix measurement can be performed. However, a practical implementation of this approach has proved to be difficult due to the requirement to vary the circular retardance. In this paper we show that by incorporating only one Faraday rotator in the polarization optics, one can generate the complete set of incident and analyzer states required for Mueller matrix measurements without the need to vary the circular retardance of the Faraday rotator.

The vector nature of light carries information that enables the non-invasive measurement of glucose in a turbid medium: blood.

The polarization properties of any medium are completely described by the sixteen element Mueller matrix that relates the polarization parameters of the light incident on the medium to that emerging from it. Measurement of all the elements of the matrix requires a minimum of sixteen measurements involving both linear and circularly polarized light. However, for many diagnostic applications, it would be useful if the polarization parameters can be quantified with linear polarization measurements alone. In this paper, we present a method based on polar decomposition of Mueller matrix for quantification of the polarization parameters of a scattering medium using the nine element (3 x 3) Mueller matrix that requires linear polarization measurements only. The methodology for decomposition of the 3 x 3 Mueller matrix is based on the previously developed decomposition process for sixteen element (4 x 4) Mueller matrix but with an assumption that the depolarization of linearly polarized light due to scattering is independent of the orientation angle of the incident linear polarization vector. Studies conducted on various scattering samples demonstrated that this assumption is valid for a turbid medium like biological tissue where the depolarization of linearly polarized light primarily arises due to the randomization of the field vector's direction as a result of multiple scattering. For such medium, polar decomposition of 3 x 3 Mueller matrix can be used to quantify the four independent polarization parameters namely, the linear retardance (delta ), the circular retardance (psi), the linear depolarization coefficient (Delta) and the linear diattenuation (d) with reasonable accuracy. Since this approach requires measurements using linear polarizers only, it considerably simplifies measurement procedure and might find useful applications in tissue diagnosis using the retrieved polarization parameters.