A Wave Plate for Every Application

The applications for wave plates are many and varied. They can find use in areas such as power attenuation of a laser and optical isolation. In biomedical applications, wave plates are used to determine the polarization of body fluids in microscopes and to correct for unwanted phase shifts. They are also used in astronomy, in the semiconductor industry and in aerospace. In short, almost every application that requires polarized light uses a wave plate to control polarization. The materials used for them are determined by the application. These options include a wide array of birefringent crystalline materials, total internal reflection retarders, polymer retarders and liquid crystals.

How a wave plate works

A wave plate produces a phase shift between the two orthogonal polarizations of a light wave. This is done via birefringence, or when the index of refraction along the slow axis differs from that along the fast axis. Common wave-plate retardances include quarter- and half-wave plates. The quarter-wave plate turns linearly polarized light into circularly polarized light with the input light at a 45° angle between the fast and slow axes. The half-wave plate is a polarization rotator as it flips the polarization direction around the fast axis of the retarder. These are manufactured from various materials, depending on the application, with costs ranging from tens to thousands of dollars.

This article comes from photonics edit released

Transient color centers in GGG crystals

Electron pulse induced absorption and their decay kinetics have been investigated in samples of GGG crystals with different starting absorption spectra.

It is shown that for all samples there appears a wide transient absorption (TA) band with two maxima in the region 14,000-17,000 v cm m 1 and 22,000-26,000 v cm m 1 . TA decay kinetics measurements in 14,000 v cm m 1 and 22,000 v cm m 1 are two-exponential (with half-time order several tens and several hundreds ns).

Analyzing the obtained results, we can suppose that low and high energy TA bands are connected with the F + (or O m ) and F transient color centers (TCC) respectively.

This article comes from tandfonline edit released

Glan Laser Polarizers

Glan Laser polarizer is made of two same birefringent material prisms that are assembled with an air space. The laser polarizer is a modification of the Glan Taylor type and is designed to have less reflection loss at the prism junction. The laser polarizer with two escape windows allow the rejected beam to escape out of the laser polarizer, which makes it more desirable for high energy lasers. The surface quality of these faces is relatively poor as compared to that of entrance and exit faces. No scratch dig surface quality specifications are assigned to these faces. The laser polarized field F1 and F2 of these is shown in the plot below.

Angular Field vs Wavelength

This article comes from foctek edit released

IR Windows Optics

IR Windows Optics are an economical choice for a variety of optical, mechanical and electronic applications. Their high transmissions, strength, chemical inertness, wear resistance, temperature stability, and low cost makes them ideal for use in high volume production applications such as:

  • High intensity UV lamps
  • Endoscopic components
  • Medical & Industrial gas analysis
  • Furnace view ports
  • Cryogenic view ports
  • UV, Visible & IR windows and cover slides
  • Pressure & Detection cells
  • Bar Code Readers
  • Photodiodes

We maintain a substantial inventory of these parts and most are available for shipment from stock. For more demanding applications, we offer Optical and Laser Quality Windows.

This article comes from melleroptics edit released

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