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Beam splitter with curved entrance and exit surfaces introduces less chromatic aberration and Seidel aberrations in some optical systems than traditional plate or block beam splitters. Spherical-surface beam splitter is used in Schmidt-type mirror objective to split converging image-forming beam so two images are formed. Small aberrations introduced are corrected by compensator plate located at or near aperture stop.
Multilayer beam splitter system yielding nearly equal broadband infrared reflectance and transmittance in the 5 to 50 micron spectral region has been developed which will significantly reduce size and cost of light path compensating devices in infrared spectral instruments.
Placing beam splitter inside existing lens minimizes aberrations. Six channel beam splitter has optical paths of lengths equal to distances traveled by rays. Lens element cemented to each of exit faces of beam splitter is optically concentric with element cemented to entrance face and with center of curvature of monocentric optical system. Beam splitter makes it possible to form separate image in each wavelength channel of interest.
Beam splitter employing birefringent optics provides either widely different or precisely equal beam ratios, it can be used with laser light source systems for interferometry of lossy media, holography, scattering measurements, and precise beam ratio applications.
Problems associated with the development of beam splitters for partitioning pump beams for pulsed dye laser systems are discussed. The operating characteristics of two types of splitters are calculated: a wedge type beam splitter and a constant-deviation prism type beam splitter. The effects of beta-angle variation on the performance of the prism type beam splitter are considered.
Fast economical fabrication produces wedge-shaped beam splitter with 0.3 micrometer edge, compared to conventional methods that have yielded 2 micrometer edges. Typical beam splitter made by new process is prism-shaped with right-triangle cross-section.
New beam splitter is a block of optically clear material with two parallel polish faces. Some of area of one surface is coated with totally reflecting layer, which may be metal or dielectric. On opposite surface, a metal coating of stepped thickness offers a different reflectivity at each step. Width and spacing of reflecting zones are chosen to accommodate angle of spacing of incidence of input beam and desired spacing of ouput beams.
Variable ratio beam splitter design and operation for lasers, using birefringent optics
Characteristics of nearly perfectly flat beam splitter for observing laser pulse shapes are discussed. Disadvantages of conventional instruments for observing properties of laser beams are described. Effects of high frequency noise on accuracy of measurement are reported.
Compact welding torch equipped with along-the-torch vision system includes cubic beam splitter to direct preview light on weldment and to reflect light coming from welding scene for imaging. Beam splitter integral with torch; requires no external mounting brackets. Rugged and withstands vibrations and wide range of temperatures. Commercially available, reasonably priced, comes in variety of sizes and optical qualities with antireflection and interference-filter coatings on desired faces. Can provide 50 percent transmission and 50 percent reflection of incident light to exhibit minimal ghosting of image.
Computations of the reflectivity, transmissivity, and efficiency properties for TE, TM, and T45 deg waves of far-infrared beam splitters and of the polarizations induced at both reflection and transmission are described. Effects of variations in the state of polarization, orientation, pointing accuracy, and wavelength of the incident light, as well as variations in refractive index and thickness of the beam splitters, are discussed. These results apply directly to Fourier interferometer-spectrometers. They can be used for optimizing the performance of these instruments. They indicate, in particular, that some advantages may be gained by the use of incident polarized light (angle of polarization smaller than about 45 deg or negative elliptical polarization) or light of large incidence angle (larger than approximately 60 deg) or both.
Jones reflection and transmission matrices representation for beam splitters, investigating reversibility and action on incident light amplitude and/or phase
Fully tilt compensated double-pass chevron beam splitter, that removes channelling effects and permits optical phase tuning, is wavelength independent and allows small errors in alignment that are not tolerated in Michelson, Machzender, or Sagnac interferometers. Device is very useful in experiments where background vibration affects conventional interferometers.
Time variations of reflectance measured for carbon dioxide laser beam splitters
Development and fabrication of pellicle beam splitter for infrared spectroscopy
Spring-loaded optical mounts maintain flatness and alinement of rigid, framed, or pellicle beam splitters over wide temperature range, despite differences in thermal expansion amoung materials. Mounts permit optical adjustments at ambient temperature even though optical system operated subsequently within few degrees of absolute zero. Mounts useful as holders for integrated-circuit master patterns, survey targets, vibrating membranes, noise- or pressure-sensing membranes, osmosis filters, and fuel-cell elements.
In this paper we will discuss the techniques that are being used to make optical beam splitter especially the same-of-the-art splitters.
Germanium optical elements at proper tilt angles minimize effects of polarization and radiance variations of background scene. Energy-division ratio is less dependent on angle of incidence of entrance beam.