Optical Coefficient Research Articles

Stoichiometric and Chiral Stacking Tailoring of Dibenzocarbazole Analog–TCNB Charge‐Transfer Cocrystals via Supramolecular Assembly for Variable Optical Behaviors

AbstractIn this paper, three new donor–acceptor complex forms (zBC) containing a helical‐shape dibenzocarbazole analog (DBCz) as the electron donor and 1,2,4,5‐tetracyanobenzene (TCNB) as the electron acceptor via a simple solution‐processing strategy are reported. The beginning components self‐assembled into supramolecular frameworks with glamorous alignment modes and different molar ratios: ≈1:1 P or M‐enantiomer for α‐cocrystal, alternated P/M‐column stacking in mesmeric 2:3 β‐cocrystal, and segregated stacking of γ‐cocrystal. As a result, α‐cocrystal exhibits bright solid‐state red fluorescent, β‐cocrystal shows significant optical waveguide behavior with a low optical loss coefficient of ≈0.018 dB µm−1, and no visual light emission is observed for γ‐cocrystal under ultraviolet radiation. Interestingly, the α‐zBC crystal is not only emissive but also chiroptically active with dissymmetry factor (glum) of 0.004. This study on chiral stacking tailoring paves a way for functional design of organic charge‐transfer complex toward application in high‐performance organic optoelectronics.

Arterial pulsation modulates the optical attenuation coefficient of skin.

Photoplethysmographic (PPG) signals arise from the modulation of light reflectivity on the skin due to changes of physiological origin. Imaging plethysmography (iPPG) is a video-based PPG method that can remotely monitor vital signs in a non-invasive manner. iPPG signals result from skin reflectivity modulation. The origin of such reflectivity modulation is still a subject of debate. Here, we have used optical coherence tomography (OCT) imaging to find whether iPPG signals may result from skin optical properties being directly or indirectly modulated by arterial transmural pressure propagation. The light intensity across the tissue was modeled through a simple exponential decay (Beer-Lambert law) to analyze in vivo the modulation of the optical attenuation coefficient of the skin by arterial pulsation. The OCT transversal images were acquired from a forearm of three subjects in a pilot study. The results show that the optical attenuation coefficient of skin changes at the same frequency as the arterial pulsation due to transmural pressure propagation (local ballistographic effect), but we cannot discard the contribution of global ballistographic effects.

Controlling Morphological Dimensions of Organic Charge‐Transfer Cocrystal by Manipulating the Growth Kinetics for Optical Waveguide Applications

AbstractPrecise fabrication of organic micro/nanostructures with regular morphology has gained a considerable concern in developing high‐performance optoelectronic devices, which is still a huge challenge to realize tunable morphology without the dependence on molecule packing arrangement. Herein, a thermodynamic/kinetic controlled self‐assembly for triphenylene‐7,7,8,8‐tetracyanoquinodimethane (TP‐TCNQ) cocrystal, with well‐defined microwires and microplates based on the same crystal structure, is proposed. With the low solution concentration of C = 5 mm, the comparable growth rates along [011] driven by π–π interaction and along [100] driven by charge‐transfer (CT) interaction facilitate the formation of thermodynamically favored shape of microplates. In contrast, the prominent CT interaction along [100] leads to the construction of microwires at kinetic state under high‐concentration solution of C = 10 mm. Furthermore, the prepared TP‐TCNQ microwires and microplates demonstrate isotropic photonic transmissions with the low optical loss coefficient of 0.033 and 0.042 dB µm−1, respectively. This strategy provides a novel avenue to finely construct the organic microcrystals with desired morphology for potential optoelectronics.

Down-conversion and up-conversion photoluminescence studies of Er3+ doped calcium zinc borosilicate glass for optical fiber amplifiers

A series of Er3+ ion doped calcium zinc borosilicate (CZBS) glass with composition 15ZnO-(10-x)CaO-10SiO2-65B2O3-xEr2O3 (x = 0.1, 0.5, 1.0, 1.5, 2.0 mol%) has been synthesized using conventional melt quenching technique. The non-crystalline nature of the as-synthesized glass is established through X-Ray diffraction (XRD). Fourier Transform Infrared (FT-IR) spectral studies present a full picture of the functional groups present in the glass system. The absorption, up-conversion (UC) and down-conversion (DC) photoluminescence (PL) and corresponding PL decay dynamics, and laser power dependent PL are investigated to better understand the optical properties and energy transfer mechanism in the glass matrices. The radiative properties such as transition probability (AR), branching ratios (βR), radiative lifetimes (τR) and near infrared (NIR) emission quantum efficiency (η) are estimated. The absorption, emission cross-sections and optical gain coefficients reveal the potential applications as laser amplifiers. The results favorably suggest the potential utility of these Er3+ doped CZBS glasses in solid-state lighting and optical communication devices.

Theoretical study on the optical properties of a phase change material blind in a double skin facade system

The use of a phase change material (PCM) blind system has great potential in mitigating overheating issues in double skin facade (DSF) systems while maintaining their optical and thermal benefits. However, there is a lack of research information available regarding the optical properties of such systems. This paper establishes a solar radiation model of PCM blinds for use in a DSF system that integrates the optical path of sunlight. The influences of the solar incidence angle, slat inclination angle, the ratio of slat distance to slat width, and slat surface material on the optical coefficient of the blind system are analyzed. The results indicate slat inclination angle significantly affects diffuse absorptance and diffuse transmittance, while solar incidence angle has little impact. Diffuse absorptance gradually increases with increasing slat inclination angle, reaching a peak at 90°, while diffuse transmittance decreases. The optical coefficient of the blind is closely related to the ratio of slat distance to slat width. The smaller the slat inclination angle, the more noticeable the difference in absorptance or transmittance of direct/diffuse solar radiation. The reflectance of the blind surface material has a significant effect on the optical coefficient. As the reflectance of the slat surface material increases, both direct absorptance and diffuse absorptance of the slat show a decreasing trend. Our results suggest that this method could be used for optical properties measurement in PCM blind system. The results of this study provide effective references for the final selection of PCM and the estimation of component dosage.

Structure and optoelectronic properties of ferroelectric PVA-PZT nanocomposites

PbZr0.8Ti0.2O3 lead zirconate-titanate was prepared using the tartrate precursor method, and (Polyvinyl alcohol (PVA)/PbZr0.8Ti0.2O3 (PZT)) thin films systems were designed by the traditional casting technique. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) methods were used to investigate the effect of the annealing temperature of PZT on the structural characteristics of the prepared composite films. PZT was annealed at various temperatures (600 °C, 700 °C, 800 °C, 900 °C, 1000 °C, and 1100 °C), and X-ray examination indicated that it included rhombohedral and tetragonal perovskite structures. Moreover, the effect of the annealing temperature on the optical band gaps, refractive index, extinction coefficient, and optical conductivity of the samples was studied using the UV–VIS spectrophotometer technique. The photoluminescence (PL) technique showed that the studied PVA/PZT films illustrated three spectra for all the samples. The Raman spectra evaluated five major Raman modes (A1(1TO), E(2TO), E (3TO+2LO)+B1, E(3TO), and A1(3LO), and T2g, which are expected in the perovskite structure. This study showed that adding PZT to the PVA matrix leads to changes in the morphological and structural properties, and the direct and indirect energy band gap (Eg) was decreased. We consider that the clustering effect in our samples increases as the crystallite size increases and prevents the vibration of the C–H bond, resulting in the disappearance of this bond in the Raman spectra. The formation of defects in synthesized compounds was analyzed using PL spectra. This system's compositional (the studied samples) dependency on optical properties makes it appropriate for optoelectronic applications.

Vibrational Spectra and Electro‐Optic Effect of Ferroelectric LiNbO3 Crystal

Though being vitally important in telecommunications and modern technology, the basic optic and especially electro‐optic (EO) properties of ferroelectric LiNbO3 crystal (LN) studied from high‐accuracy first‐principles calculation are still not satisfactory. Herein, the electronic structure and vibrational spectra of LN are calculated by the CRYSTAL program. With a hybrid B3LYP functional, the bandgap of 4.8473 eV, refractive indices of no = 2.2339, ne = 2.1440, and nonlinear optical coefficients of d11 = 2.1 pm V−1, d31 = −4.35 pm V−1, and d33 = −27.2 pm V−1 are obtained. It is found that the phonon vibrations are asymmetric along especially the polar axis and the numerically calculated frequencies are strongly dependent on displacement parameters chosen. By averaging displacements to both the positive and negative directions, the obtained vibrational frequencies show excellent agreement to the measured ones except in the range of 320–370 cm−1 where the assignments of the observed ones are in dispute due to extreme low spectral intensities. Based on the calculated vibrational spectra, the clamped dielectric constants of and and clamped EO coefficients of = 27.08 pm V−1, = 9.60 pm V−1, = −5.14 pm V−1, and = 16.90 pm V−1 are obtained.

Intraoperative application of optical coherence tomography for lung tumor.

On-site instant determination of benign or malignant tumors for deciding the types of resection is crucial during pulmonary surgery. We designed a portable spectral-domain optical coherence tomography (SD-OCT) system to do real-time scanning intraoperatively for the distinction of fresh tumor specimens in the lung. A total of 12 ex vivo lung specimens from six patients were enrolled. Three patients were diagnosed with invasive adenocarcinoma (IA), while the others were benign. After OCT-imaged reconstruction, we compared the qualitative morphology of OCT and histology among malignant, benign, and normal tissues. In addition, through analysis of the quantitative data, a discrete difference in optical attenuation coefficients around the junctional surface was shown by our data processing. This study demonstrated a feasible OCT-assisted resection guide by a rapid on-site tumor diagnosis. The results indicate that future deep learning of OCT-captured image systems able to improve diagnostic and therapeutic efficiency is warranted.

Nondestructive label-free detection of peritumoral white matter damage using cross-polarization optical coherence tomography

To improve the quality of brain tumor resections, it is important to differentiate zones with myelinated fibers destruction from tumor tissue and normal white matter. Optical coherence tomography (OCT) is a promising tool for brain tissue visualization and in the present study, we demonstrate the ability of cross-polarization (CP) OCT to detect damaged white matter and differentiate it from normal and tumor tissues. The study was performed on 215 samples of brain tissue obtained from 57 patients with brain tumors. The analysis of the obtained OCT data included three stages: 1) visual analysis of structural OCT images; 2) quantitative assessment based on attenuation coefficients estimation in co- and cross-polarizations; 3) building of color-coded maps with subsequent visual analysis. The defining characteristics of structural CP OCT images and color-coded maps were determined for each studied tissue type, and then two classification tests were passed by 8 blinded respondents after a training. Visual assessment of structural CP OCT images allows detecting white matter areas with damaged myelinated fibers and differentiate them from normal white matter and tumor tissue. Attenuation coefficients also allow distinguishing all studied brain tissue types, while it was found that damage to myelinated fibers leads to a statistically significant decrease in the values of attenuation coefficients compared to normal white matter. Nevertheless, the use of color-coded optical maps looks more promising as it combines the objectivity of optical coefficient and clarity of the visual assessment, which leads to the increase of the diagnostic accuracy of the method compared to visual analysis of structural OCT images. Alteration of myelinated fibers causes changes in the scattering properties of the white matter, which gets reflected in the nature of the received CP OCT signal. Visual assessment of structural CP OCT images and color-coded maps allows differentiating studied tissue types from each other, while usage of color-coded maps demonstrates higher diagnostic accuracy values in comparison with structural images (F-score = 0.85-0.86 and 0.81, respectively). Thus, the results of the study confirm the potential of using OCT as a neuronavigation tool during resections of brain tumors.

Automated segmentation and quantification of calcified drusen in 3D swept source OCT imaging.

Qualitative and quantitative assessments of calcified drusen are clinically important for determining the risk of disease progression in age-related macular degeneration (AMD). This paper reports the development of an automated algorithm to segment and quantify calcified drusen on swept-source optical coherence tomography (SS-OCT) images. The algorithm leverages the higher scattering property of calcified drusen compared with soft drusen. Calcified drusen have a higher optical attenuation coefficient (OAC), which results in a choroidal hypotransmission defect (hypoTD) below the calcified drusen. We show that it is possible to automatically segment calcified drusen from 3D SS-OCT scans by combining the OAC within drusen and the hypoTDs under drusen. We also propose a correction method for the segmentation of the retina pigment epithelium (RPE) overlying calcified drusen by automatically correcting the RPE by an amount of the OAC peak width along each A-line, leading to more accurate segmentation and quantification of drusen in general, and the calcified drusen in particular. A total of 29 eyes with nonexudative AMD and calcified drusen imaged with SS-OCT using the 6 × 6 mm2 scanning pattern were used in this study to test the performance of the proposed automated method. We demonstrated that the method achieved good agreement with the human expert graders in identifying the area of calcified drusen (Dice similarity coefficient: 68.27 ± 11.09%, correlation coefficient of the area measurements: r = 0.9422, the mean bias of the area measurements = 0.04781 mm2).

Topological insulator-based nonlinear optical effects and functional devices

Topological insulators (TIs) are a new type of electronic material with the insulating bulk state and topologically protected conducting surface/edge state. TI materials exhibiting outstanding optical properties containing high carrier mobility, ultrahigh refractive index, wide operating spectral range, and dynamic tunability play an important role in optical functional devices. Especially, the TI materials with special topological energy bands possess high nonlinear optical coefficient, superior to conventional semiconductor and two-dimensional materials. The nonlinear optical characters of TIs are expected to realize highly efficient nonlinear optical conversion, nonlinear absorption, and all-optical switching, terahertz emission. TIs will provide a new platform for the interaction between light and matter as well as the development of nonlinear optics. In this review, we conclude current advances about some research on TI-based nonlinear optical effects and related devices, and give a prospect of potential applications for TIs in nonlinear optics.

Effect of particle and pore morphology on optical transmission of yttria based laser host ceramics: A small-angle scattering investigation

Transparent and nearly opaque Nd: YAG and Nd: Y2O3 laser host ceramics synthesized by both co-precipitation (COP) and solid-state reaction (SS) routes are investigated using the scanning electron microscopy (SEM) and small-angle scattering (SAS) technique. Studies revealed that ceramic pellets of Nd: YAG and Nd: Y2O3 contain bi-modal pores with 〈D〉 ∼ 120 nm-230 nm and 28–58 nm and the pore structure is independent of the method of preparation. The porosity values of all the ceramic pellets are calculated and it is found that SS-synthesized pellets remained nearly 10 times more porous than those obtained from the COP method. These results are attributed to the presence of hard non-sinterable aggregates in the SS ceramic pellets as observed in SEM pictures. Further, the optical attenuation coefficients (at λ = 300 nm, 450 nm, 645 nm and 1000 nm) are also calculated using the parameters obtained from SAS results and the values are found to be 22.2 cm−1, 4.5 cm−1, 0.87 cm−1, 0.48 cm−1 for YAG and 34.8 cm−1, 3.5 cm−1, 1.20 cm−1, 0.78 cm−1 for Y2O3 ceramic pellets synthesized by COP method. These attenuation coefficient well corroborate with the optical transmission studies. Our study shows that SAS as an excellent technique to calculate porosity of the technologically important laser host ceramics and correlate optical properties with their pore morphology.

In vivo characterization of cerebrovascular impairment induced by amyloid β peptide overload in glymphatic clearance system using swept-source optical coherence tomography.

Antiamyloid ( ) immunotherapy is a promising therapeutic strategy for Alzheimer's disease (AD) but generates large amounts of soluble peptides that could overwhelm the clearance pathway, leading to serious side effects. Direct implications of in glymphatic drainage transport for cerebral vasculature and tissue are not well known. Studies are needed to resolve this issue and pave the way to better monitoring abnormal vascular events that may occur in -modifying therapies for AD. The objective is to characterize the modification of cerebral vasculature and tissue induced by soluble abundantly present in the glymphatic clearance system. peptide was injected intracerebroventricularly and swept-source optical coherence tomography (SS-OCT) was used to monitor the progression of changes in the brain microvascular network and tissue in vivo over 14 days. Parameters reflecting vascular morphology and structure as well as tissue status were quantified and compared before treatment. Vascular perfusion density, vessel length, and branch density decreased sharply and persistently following peptide administration. In comparison, vascular average diameter and vascular tortuosity were moderately increased at the late stage of monitoring. Endpoint density gradually increased, and the global optical attenuation coefficient value decreased significantly over time. burden in the glymphatic system directly contributes to cerebrovascular structural and morphological abnormalities and global brain tissue damage, suggesting severe deleterious properties of soluble cerebrospinal fluid- . We also show that OCT can be used as an effective tool to monitor cerebrovascular dynamics and tissue property changes in response to therapeutic treatments in drug discovery research.

Study of the Optical properties for CdS before and after irradiated by CO2 laser for different exposure times

Cadmium sulphide (CdS) thin films were deposited on glass substrates using thermal vacuum evaporation technique at pressure (10-6) Torr at room temperature then samples irradiated by CO2 laser of power (1 watt) and wave length (10.6) μm at distance 10 cm from the source during different exposure times (3, 5, 10, 15) sec. The absorbance spectra was recorded using UV-visible spectrophotometer .Optical properties such as transmission , reflection ,absorption coefficient (α), optical band gap (Eg), extinction coefficient (K), refractive index (n), and complex dielectric constants (er&ei) were evaluated from absorbance spectra. The results shows that the laser irradiation cause increased in reflectance R, absorption coefficient a, the extinction coefficient K, the refractive index n and the real part and imaginary part of dielectric constant while irradiation cause decrease in the transmittance T and the value of the energy gap Eg.

Calibration methods and uncertainties estimation of WEST infrared thermography diagnostics

This paper presents the method toward quantifying the global uncertainty on the blackbody temperature measurement from the infrared (IR) diagnostics of WEST. To address this goal, the main functional elements of the IR diagnostics are identified. Then the temperature calibration and calculation principles are presented and analysed to extract the main potential uncertainty contributors, such as the optical transmission coefficients and their stray lights, or the accuracy of temperature references used for calibration. These contributors are individually estimated, or experimentally measured when a supposed effect on the overall uncertainty is identified, like environmental conditions or parasitic radiations. In particular, effects of environmental temperature on the transmission lines and camera is thoroughly studied. All contributions are then aggregated in the uncertainty propagation calculation and results in an overall temperature uncertainty versus the temperature estimation. The uncertainty is in the range of 5–10% for blackbody temperatures above 200 °C, and progressively worsens when temperature decreases.

Ab-initio DFT calculations and experimental investigations into optoelectronic and structural properties of Ca9Al(PO4)7:Sm3+ orange phosphor

Nanocrystalline phosphors of composition Ca9Al(PO4)7:xSm3+ (x = 0.01–0.16) were successfully synthesized using a urea-assisted highly efficient solution combustion technique. The structural, morphological, and photoluminescence features of the series of white powdered samples were studied using powder X-ray diffraction, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and photoluminescence characterization techniques. The structural framework and crystal phase purity of Ca9Al0.90Sm0.10(PO4)7 phosphor were investigated by Rietveld refinement analysis. The results showed that the replacement of Al3+ ions with Sm3+ ions in Ca9Al0.90Sm0.10(PO4)7 nanophosphor didn't alter the host lattice crystal structure and a trigonal lattice having R3c(161) space group was established. Meanwhile, the average particle size evaluated from the Scherrer equation was further confirmed by transmission electron microscopic studies revealing a size domain ranging from 35-60 nm. Structural optimization of the pure host via first-principle routing disclosed the density of states and electronic band structure having a band gap of 4.738 eV, which was found to be quite comparable to the experimentally observed value (4.37 eV) from the diffuse reflectance spectra. Many key optical properties, such as optical conductivity, extinction coefficient, loss function, and refractive index were determined by using a calculated dielectric function. Furthermore, photoluminescence studies inferred that 10 mol% of Sm3+ ion in Ca9Al(PO4)7 host matrix gave the best luminescence emission intensity. Detailed photoluminescent analysis of Ca9Al(PO4)7:xSm3+ phosphors demonstrated that on excitation at 401 nm, an intense reddish-orange emission was received at 600 nm (4G5/2 → 6H7/2 transition). The critical distance for energy migration came out to be 22 Å which strongly favors the mechanism behind luminescence quenching as dipole-quadrupole interactions resulting from the over-doping of activator ions. The chromaticity coordinates (0.5216, 0.3630) were obtained using MATLAB computations. These results favor the applicability of Sm3+ doped Ca9Al(PO4)7 phosphors as the reddish-orange emitter in near-ultraviolet excited white light-emitting diodes.

Synthesis and characterization of (Sb0.05In0.95)Se crystals

The antimony doped indium selenide (Sb0.05In0.95)Se crystals have been grown using the direct vapour transport (DVT) technique. The grown (Sb0.05In0.95)Se crystals have been characterized by estimating its structural, optical and electrical properties using appropriate techniques. The (Sb0.05In0.95)Se crystal has a hexagonal crystal structure with a preferred orientation along the (004) direction from the X-ray diffraction (XRD) spectra. Also, the micro-structural parameters (crystallite size, lattice strain, dislocation density, domain population) have been analysed from XRD spectra. The optical parameters (optical band gap, extinction coefficient and refractive index) have been calculated from UV–vis absorption spectrum. The resulting optical direct band gap is 1.51 eV. The activation energy value of 0.71 eV has been obtained from resistance-temperature observations of (Sb0.05In0.95)Se crystal.

Flexible Optical Waveguides in Heterocyclic Schiff Base Self-Assembled Hydrogen-Bonded Solvates

Flexible fluorescent crystalline materials exhibit both mechanical and optical properties and have received great attention due to their potential applications in flexible optical devices. Simultaneously adjusting the mechanical and optical properties of crystalline materials remains interesting and challenging. In the present work, a guest molecule was introduced via hydrogen-bonded solvation, which achieved excellent mechanical elasticity and higher fluorescence emission than that of the host heterocyclic Schiff base molecule crystal itself. The crystal structure–property relationship and the molecular mechanism of the elasticity were then investigated in detail. It revealed that solvent molecules play a key role in changing both the stacking of fluorescent molecules and the interaction energy framework. In addition, the flexible fluorescent solvate exhibits a good waveguide property. A bent crystal was found to have a larger optical loss coefficient than a straight crystal. Furthermore, the size effect on the optical loss coefficient of the waveguide was discussed in which the optical loss coefficient decreases as the sizes increase. Such a size effect is usually neglected in waveguide material research and should be complemented in the performance evaluation of optical waveguides.

The Kurtz-Perry Powder Technique Revisited: A Study of the Effect of Reference Selection on Powder Second-Harmonic Generation Response.

The accurate evaluation of nonlinear optical (NLO) coefficient, the main parameter affecting light conversion efficiency, plays a crucial role in the development of NLO materials. The Kurtz-Perry powder technique can evaluate second-harmonic generation (SHG) intensity in pristine powder form, saving a significant amount of time and energy in the preliminary screening of materials. However, the Kurtz-Perry method has recently been subject to some controversy due to the limitations of the Kurtz-Perry theory and the oversimplified experimental operation. Therefore, it is very meaningful to revisit and develop the Kurtz-Perry technique. In this work, on the basis of introducing the light scattering effect into the original Kurtz-Perry theory, the theoretical expression of second-harmonic generation intensity with respect to band gap and refractive index are analyzed. In addition, the reference-dependent SHG measurements were carried out on polycrystalline LiB3O5 (LBO), AgGaQ2 (Q = S, Se), BaGa4Q7 (Q = S, Se), and ZnGeP2 (ZGP), and the results of SHG response emphasize the importance of using appropriate references to the Kurtz-Perry method. In order to obtain reliable values of nonlinear coefficients, two criteria for selecting a reference compound were proposed: (1) it should possess a band gap close to that of the sample to be measured and (2) it should possess a refractive index close to that of the sample to be measured. This work might shed light on improvements in accuracy that can be made for effective NLO coefficients obtained using the Kurtz-Perry method.

Surface morphology and optical properties of thin films of plasma polymerized methyl acrylate

Thermally stable plasma polymerized methyl acrylate (PPMA) thin films are fabricated onto spotless glass substrates by AC power plasma polymerization technique. Field emission scanning electron micrographs of these films exhibit clusters/agglomerations on the surface. Energy dispersive x-ray analysis confirms the existence of 52.38, 52.63 and 51.55% of carbon and 47.62, 47.31 and 46.45% of oxygen, respectively in 170, 230 and 290 nm thick PPMA films. The molecular vibrations of various natures observed by attenuated total reflectance Fourier transform infrared spectroscopy of methyl acrylate and PPMA represent that the percentage of hydrophilic groups is smaller than the hydrophobic groups. Thermogravimetric analyses demonstrate that the major weight loss occurs in the temperature range from 500 to 850 K. Ultraviolet–visible spectroscopy demonstrates that the allowed direct energy band gap varies from 3.77 to 3.83 eV, whereas the indirect energy band gap alters from 3.40 to 3.48 eV with film thicknesses from 120 to 290 nm. Other optical parameters such as Urbach energy, refractive index, optical extinction coefficient, dielectric constants, quality factor, and skin depth have also been investigated for the PPMA thin films to elucidate their suitability in optoelectronic devices.