Preferred Language
Articles
/
bsj-554
EXTENSION OF HIGH REFLECTANCE BAND WIDTH FOR FAR INFRARED SPECTRAL REGION : (1)
...Show More Authors

Extension of bandwidth for high reflectance zone for the spectral region (8-14pm) was studied adapting the concept of contiguous and overlapping high reflectance stacks. Computations was carried out using the modified characteristic matrix theory restricted to near-normal incidence of light on dielectric , homogenous and isotropic symmetrical stack. Certain precautions must be taken in the choice of stacks to avoid deep —reflectance minima from developing within the extended high reflectance region. Results illustrate that the techniques of extending the high reflectance regions are applicable not only to mirrors , but also to short-and long-edge filter and to narrow band pass filters.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Expand bandwidth high reflectivity of the far infrared region
...Show More Authors

Was expanded display high reflectivity of the spectral remote infrared (m j 14-8) adoption order Alcolmtin ????????? thickness optical northeastern quarter wavelength and compared with results of previous studies based Aldrashalhalah on Ndharah matrix distinctive amended and fall of light close to the vertical arrangement multilayer materials buffer and in thin films homogeneous and uniform properties deposited on germanium basis results showed that the best choice for governments and their kills to expand bandwidth high reflectivity is much easier for the infrared than the area visible in addition to the order of these stacks is the cornerstone of the filters other visual...

View Publication Preview PDF
Publication Date
Tue Jan 01 2019
Wide-range tunable subwavelength band-stop filter for the far-infrared wavelengths based on single-layer graphene sheet
...Show More Authors

Scopus (4)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Thu Jan 01 2015
Journal Name
International Journal Of Application Or Innovation In Engineering & Management
Far Infrared Photoconductive Detector Based on Multi-Wall Carbon Nanotubes
...Show More Authors

Far infrared photoconductive detectors based on multi-wall carbon nanotubes (MWCNTs) were fabricated and their characteristics were tested. MWCNTs films deposited on porous silicon (PSi) nanosurface by dip and drop coating techniques. Two types of deposited methods were used; dip coating sand drop –by-drop methods. As well as two types of detector were fabricated one with aluminum mask and the other without, and their figures of merits were studied. The detectors were illuminated by 2.2 and 2.5 Watt from CO2 of 10.6 􀀀m and tested. The surface morphology for the films is studied using AFM and SEM micrographs. The films show homogeneous distributed for CNTs on the PSi layer. The root mean square (r.m.s.) of the films surface roughness in

... Show More
Publication Date
Sun Dec 07 2014
Journal Name
Baghdad Science Journal
Modeling and optimum design band pass filter for mid IR region
...Show More Authors

In this study, we design narrow band pass filter for window (3_5) ?m dependent on the needle optimization method , and a comparison with global designs published -Also, the effect of change parameter design on the optical performance of filter was studded and being able to overcome the difficulties of the design.In this study, the adoption of homogeneous optical properties materials as thin film depositing on a substrate of germanium at wavelength design (? = 4 ?m). For design this kind of filters we used advanced computer program (Matlab )to build a model design dependent both matrix characteristic and Needle technique. In this paper we refer to the type of Mert function , which is used for correct optical performance acces

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Tue Sep 01 2009
Journal Name
Journal Of Nonlinear Optical Physics & Materials
SPECTRAL WIDTH VARIATION OF ULTRASHORT LASER PULSES IN MONOMODE OPTICAL FIBERS
...Show More Authors

Femtosecond laser pulse propagation in monomode optical fibers is demonstrated and investigated numerically (by simulations) and experimentally in this paper. A passively mode locked Nd:glass laser giving a pulse duration of about 200 fsec at 1053 nm wavelength and 120 mW average optical power with 100 MHz repetition rate is used in the experimental work. Numerical simulations are done by solving the nonlinear Schrödinger equation with the aid of Matlab program. The results show that self phase modulation (SPM) leads to compression of the spectral width from 5 nm to 2.1 nm after propagation of different optical powers (34, 43, 86 and 120 mW) in fibers of different length (5, 15, 35 m). The varying optical powers produced a varying

... Show More
View Publication
Scopus (1)
Scopus Clarivate Crossref
Publication Date
Sat Nov 28 2020
Journal Name
Iraqi Journal Of Science
Design of Anti-Reflection Coatings for Application in the Infrared Region (10.6 micron)
...Show More Authors

In this research, anti-reflection coatings consisting of single and double layers were designed in the IR (8 – 14μm) region to reduce the unwanted reflections of germanium (Ge) substrate. The reflectance of Ge substrate was about 36% per surface. These values were reduced reasonably by using single and double layer anti-reflection. The used layers were promoted in their performance by changing their thickness and refractive indices. The results indicated that the suggested structures are very efficient in reducing the reflectance of the Ge substrates in the selected region. The performance of the double layer antireflection coatings of ZnSe, BaF2 and BiF3 on Ge substrates is presented.

View Publication Preview PDF
Scopus (3)
Crossref (2)
Scopus Crossref
Publication Date
Mon Jun 01 2015
Journal Name
The European Physical Journal Applied Physics
A carbon nanotubes photoconductive detector for middle and far infrared regions based on porous silicon and a polyamide nylon polymer
...Show More Authors

View Publication
Scopus (3)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Mon Jun 01 2009
Journal Name
Al-khwarizmi Engineering Journal
Breast Tumor Diagnosis Using Diode Laser in Near Infrared Region
...Show More Authors

In the last years, new non-invasively laser methods were used to detect breast tumors for pre- and postmenopausal females. The methods based on using laser radiation are safer than the other daily used methods for breast tumor detection like X-ray mammography, CT-scanner, and nuclear medicine.  

      One of these new methods is called FDPM (Frequency Domain Photon Migration). It is based on the modulation of laser beam by variable frequency sinusoidal waves. The modulated laser radiations illuminate the breast tissue and received from opposite side.

      In this paper the amplitude and the phase shift of the received signal were calculated according to the orig

... Show More
View Publication Preview PDF
Publication Date
Wed Apr 01 2020
Journal Name
Plant Archives
Effect of soil salinity on spectral reflectance of red and nir wavelengths in al-salamiyat project
...Show More Authors

Scopus (4)
Scopus
Publication Date
Mon Oct 11 2021
Journal Name
Nano Hybrids And Composites
Far Infrared Laser Detector Based on Multi-Walled Carbon Nanotubes and Blend of (Polyaniline - Polymethyl Methacrylate) Polymers with Methyl Blue Dye for Photoconductive Applications
...Show More Authors

Infrared photoconductive detectors working in the far-infrared region and room temperature were fabricated. The detectors were fabricated using three types of carbon nanotubes (CNTs); MWCNTs, COOH-MWCNTs, and short-MWCNTs. The carbon nontubes suspension is deposited by dip coating and drop–casting techniques to prepare thin films of CNTs. These films were deposited on porous silicon (PSi) substrates of n-type Si. The I-V characteristics and the figures of merit of the fabricated detectors were measured at a forward bias voltage of 3 and 5 volts as well as at dark and under illumination by IR radiation from a CO2 laser of 10.6 μm wavelengths and power of 2.2 W. The responsivity and figures of merit of the photoconductive detector

... Show More
View Publication
Crossref (1)
Clarivate Crossref