Design and Synthesis of cdwo4 crystals

Sb3+-activated cdwo4 crystals phosphors were designed according to sp energy levels regularities of Sb3+ ion in some inorganic compounds. The sp energy levels regularities of Sb3+ in dozens of compounds were established with the aid of the dielectric theory of the chemical bond for complex crystals: EA = 6.2187−1.7584he, EB = 7.019−1.957he, EC = 7.259−1.964he.

Environmental factor he of Cd site was calculated to be 1.6583 with the refined crystal structure and refractive index of cdwo4 crystals:Sb3+. Sb3+-doped cdwo4 crystals was synthesized through a precipitation method and its structure was refined with the General Structure Analysis System. The transition energy of A band of Sb3+ in cdwo4 crystals can be predicted to be 3.312 eV (374 nm), according to the relationship equation between EA and environmental factor he.

By monitoring the 521 nm emission band, the excitation spectrum gives a weak excitation band peaking at 355 nm, which was assigned to the 1S0–3P1 transition of Sb3+ according to our prediction. Thus, Sb3+-doped cdwo4 crystals phosphor was designed and synthesized successfully based on sp energy levels regularities of Sb3+ ion. This work is a great help to understand the spectroscopy of Sb3+ ion and will be useful for the design and development of Sb3+-doped phosphors for applications.

This article comes from onlinelibrary edit released

Standard long wave pass optical filters

Long wave pass optical filters provide a sharp cut-off below a particular wavelength. Often used for order sorting, they isolate broad regions of the spectrum, simultaneously providing high transmission of desired energy, and deep rejection of unwanted energy.

Constructed of hard, durable first-surface dielectric coatings on optical-quality IR-transmitting substrates, these long wave pass optical filters will withstand normal cleaning and handling associated with any high-quality optical component.

For your convenience and economy, we offer the filters in two standard sizes: 25mm and 50mm dia. However, we can produce custom sizes and shapes, as well as custom optical characteristics.

We also offer long pass filter in the UV and visible wavelength ranges, including steep-edge long pass filters.

This article comes from andovercorp edit released

Cleaning the Laser Mirror in your Epilog Laser System

Ensuring your laser mirror are clean will help your laser system perform its best. If smoke, resin, or other contaminants are allowed to accumulate too heavily, they will reduce the available laser power and may cause damage. Dirty laser mirror can also greatly reduce the engraving and cutting quality of your machine so it’s very important to keep them clean.

The two optical components most likely to require cleaning are the focus lens and the mirror directly above it. The lens and mirror are a single assembly, and can be removed from the machine for cleaning, but it is generally not recommended.

Here we’ll walk you through the steps of cleaning this crucial component of your laser system.

You’ll need:

  • Epilog-supplied lens cleaner.
    You may also use distilled white vinegar (ten parts water, one part white vinegar) or pure grain alcohol (such as Everclear) if you do not have Epilog-supplied lens cleaner. These liquids are pure in nature and readily available.
  • High-quality cotton swabs.

To clean the laser mirror use a high-quality cotton swab moistened with the laser mirror cleaner supplied in the accessory kit. Please read the label on the bottle carefully. Rubbing alcohol should be used only to remove fingerprints. If you run out of the cleaner supplied by Epilog, acetone can be used as a temporary measure, but should not be used for regular cleaning as it contains impurities, which can contaminate the laser mirror.

Wet the swab thoroughly with the solvent, and then blot it against a piece of cotton so that it is no longer soaking-wet. Then daub the optic gently, rotating the swab after each daub to expose clean cotton to the surface, until the optic is free of visible contamination. At that point, prepare a fresh swab and clean the surface with a gentle zigzag motion across it. Avoid any hard “scrubbing” of the surface, especially while there are visible particles on it, and try not to use repetitive circular motions. When you are done, be careful to remove any cotton threads that may have snagged on the mountings. Allow the laser mirror to dry before you operate your engraver.

In addition to the focus lens and the mirror directly above it, there is a mirror located on the left side of the machine and is mounted to the X-beam.

This mirror is very well protected and should not need regular cleaning. It can be accessed with a cotton swab if it does need cleaning. The photo below shows where this mirror is located in relation to the X-beam and carriage.

Regular system maintenance is crucial to the longevity and performance of your machine. By performing just a few simple tasks on a regular basis you can add years to the life of your laser. For more maintenances tips, be sure to check out Epilog’s whitepaper System Maintenance: Keeping a clean and productive laser system.

This article comes from epiloglaser edit released

MWIR Lens Design

We hold sophisticated algorithm for optics design optimization process back-up by powerful workstations. The unique optimization allows reduced complexity in the optical element/system spec, which finally will insure the manufacturing feasibility. It also allows higher yields with almost no performance degradation. In addition, we have extensive experience in mechanical and Opto-Mechanical design which includes tolerance, thermal and stray light analysis.

With the great assistance of our IR components manufacturing capability, we are confident to provide our customer the most affordable design solution without performance compromise. Please refer to our IR components fabrication capability (IR components link here) for further information. We provide 6 weeks typical prototyping lead time for custom MWIR lens design, including assembly and testing, Trioptics MTF chart provided. For complicated asphere/DOE involved system, please contact our optical engineer to discuss your specification for helpful and informative consultation section.

Off-the-shelf Mid-wave (MWIR) lenses feature cooled technology, which offers very high sensitivity and better transmission. We have our standard design but we also offer customized design to meet our customer needs. These lenses include EFL from 9.05mm to 100mm and function in the wavelengths of 2 – 5μm and 3 – 5μm. The F number is 2. The lenses also cover various detector sizes from 15.36×12.29 to 320×240 pixels. The front lens is coated with Hard Diamond coating and mounted with aluminum mounts.

Effects of packaging SrI2(Eu) scintillator crystals

Recent renewed emphasis placed on gamma-ray detectors for national security purposes has motivated researchers to identify and develop new scintillator materials capable of high energy resolution and growable to large sizes.

We have discovered that SrI2(Eu) scintillators has many desirable properties for gamma-ray detection and spectroscopy, including high light yield of ∼90,000 photons/MeV and excellent light yield proportionality. We have measured <2.7% FWHM at 662 keV with small detectors (<1 cm3) in direct contact with a photomultiplier tube, and ∼3% resolution at 662 keV is obtained for 1 in.3 crystals. Due to the hygroscopic nature of SrI2(Eu) scintillators, similar to NaI(Tl), proper packaging is required for field use.

This work describes a systematic study performed to determine the key factors in the packaging process to optimize performance. These factors include proper polishing of the surface, the geometry of the crystal, reflector materials and windows. A technique based on use of a collimated 137Cs source was developed to examine light collection uniformity.

Employing this technique, we found that when the crystal is packaged properly, the variation in the pulse height at 662 keV from events near the bottom of the crystal compared to those near the top of the crystal could be reduced to <1%. This paper describes the design and engineering of our detector package in order to improve energy resolution of 1 in.3-scale SrI2(Eu) scintillators crystals.

This article comes from sciencedirect edit released

Medical Filter – IPL Filter

IPL filter is the key optical element for IPL (intense Pulsed Light) machine, which filters the UV wave and reserve the useful wave from 400nm to 1200nm for cosmetic laser, such as photrevujenation, hair removal, vascular and acne treatment. The available wavelength are 550, 560, 570, 590, 615, 645, 695, 755,780 nm.

  • Material:N-BK7 Grade A optical glass, Fused silica, Sapphire crystal.
  • Dimension Tolerance:+/-0.1(General), +/-0.01(High Precision)
  • Thickness Tolerance:+/-0.2 (General), +/-0.005(High Precision)
  • Surface Quality:60/40
  • Clear Aperture:>90%
  • Parallelism<3 arc min. (General) , <5 arc sec.(High Precision)
  • Wavefront Distortion(per 25mm@633nm): λ/2 (General) , λ / 8(High Precision)
  • Bevel(face width x45°):0.2~0.5mm

Available wavelength: 515 ~ 1200, 530 ~ 1200, 550 ~ 1200, 560~ 1200, 570 ~ 1200, 590 ~ 1200,
615 ~ 1200, 645 ~ 1200, 695 ~ 1200, 755 ~ 1200, 780 ~ 1200 nm

Laser Line Bandpass Filter

Laser Line bandpass Filters transmit a well-defined center wavelength of light, with band pass width, while blocking the other unwanted radiation. Central Wavelength from 350 nm to 1550 nm, 350nm, 488nm, 515nm, 560nm, 590nm, 640nm, 755nm, 850nm, 980nm, 1060nm, 1310nm, 1550nm laser line type.
1nm, 3nm, 10nm, 12nm, 25nm, 40nm, and 70 nm Bandpass width etc.

This article comes from wavelength-tech edit released

Common Laser Crystals Dopants

Laser crystals are typically single crystals (monocrystalline material) which are used as gain media for solid-state lasers. In most cases, they are doped with either trivalent rare earth ions or transition metal ions. These ions enable the crystal to amplify light at the laser wavelength via stimulated emission, when energy is supplied to the crystal via absorption of pump light (→ optical pumping).

Compared with doped glasses, crystals usually have higher transition cross sections, a smaller absorption and emission bandwidth, a higher thermal conductivity, and possibly birefringence. (The article on laser crystals versus glasses discusses the differences in more detail.) In some cases, monocrystalline laser materials may be replaced with ceramic gain media, which have a fine polycrystalline structure.

This article comes from rp-photonics edit released

Well-type NaI(Tl) detector efficiency using analytical technique


• A new analytical approach for calculation of the full-energy peak efficiency is deduced.
• The method depends on the calculation of the photon path length.
• Separate calculation of factors which related to photon attenuation is introduced.
• The effective solid angle between source-to-detector is calculated.
• Remarkable agreement between measured and calculated efficiencies was achieved.

Well-type detectors play an important role in qualitative and quantitative analysis of low-activity samples, thanks to their pronouncedly high efficiency; this is particularly the case with scintillation detectors. In this work a theoretical approach to calculations of full-energy peak efficiencies of well-type detectors is elaborated.

The approach is based on the concept of the effective solid angle and the efficiency transfer principle. In parallel, ANGLE 4 software was employed to the same aim, using point sources positioned on 2″ × 2″ NaI(Tl) detector axis outside the detector well cavity. The theoretically obtained and ANGLE 4 calculated efficiency values were compared to the measured ones. These comparisons supported/confirmed both the theoretical concept and ANGLE 4 Software validity in well-type scintillation detectors calibration.

This article comes from science-direct edit released

Lasers used to form crystals

Our customers are of course laser experts but, when additional technical or applications support is required, we can call on many years of experience to assist them.

Our range of crystals for lasers is complemented by our range of high power laser diodes, electro-optic and non-linear crystals. More details can be found on our home page.

For medical solid state lasers we provide a full range of sizes, shapes, and quantities of ruby crystals for lasers, Er:YAG and CTH:YAG to meet the precise specifications of the medical laser manufacturer. Ruby lasers are used for cosmetic dermatology to remove unwanted hair, tattoos, portwine stains and similar skin blemishes. The advantage ruby laser treatment holds over other procedures is the 694 nm output does not affect normal, healthy skin in or around the treated area.

The series of medical YAG compositions generate output at discrete wavelengths between 2.1 and 3.0 microns. This spectrum couples well into water and body fluids. By selection among the different compositions in the medical YAG materials series, laser systems can be optimized for soft or hard tissue applications.

For industrial & high power solid state lasers we offer a full range of Nd:YAG crystals for lasers. Systems designers may select from several levels of dopant concentrations and rod configurations to optimize the performance of each laser system. Our range of dopants extends from 0.3%Nd through 1.4%Nd.

For lower power solid state lasers we have Nd:YVO4 available. This material has been growing in popularity because of its high gain low lasing threshold and high absorption coefficient at pumping wavelengths, resulting from th excellent fit of the neodymium dopant in the crystal lattice. We offer dopant concentrations from 0.1% upwards and a choice of coatings are available. As an alternative, Nd:GdVO4 can be used, the material benefitting from a much higher thermal conductivity and improved improved absorption.

For tunable lasers, titanium doped sapphire is an optically pumped, solid state laser material with an indefinitely long stability and useful life. It is the most widely used crystal for wavelength tunable lasers. Ti:sapphire crystals for lasers combine the robust properties of sapphire with the broadest tunable range of any known laser material. Laser output can be generated over the entire spectrum from 650 to 1100 nm. Frequency doubling the output provides tunability across the blue-green region of the visible spectrum.

For femtosecond and research lasers, titanium doped sapphire is a versatile crystal. Short, femto-second pulses can be produced successfully across the tunable range making Ti:sapphire ideal for ultra-fast spectroscopy. Other uses include nuclear fusion studies, micro-machining and very high speed read/write memory applications.

This article comes from roditi edit released

What Does a Ultraviolet Filter Do?

Put simply, UV filters reduce haziness created by ultraviolet lights.

Lets have a quick physics lesson. Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than x-rays, in the range 10 nm to 400 nm. If you own a film camera then you might know the reason you use a UV filter.

It all down to colour film having 3 sensitive layers, one to red, one to blue and one to green (RBG). The blue layer responses to UV light as well as blue light, if you take an image which lots of UV light the blue layer becomes overexposed and your image takes a blue colour.

You can buy different strength UV filters, stronger UV filters will stop more blue light and will leave the image with a slight yellow tone.

This article comes from photography edit released