Waveplate
Waveplates (retardation plates or phase shifters) are made from materials which exhibit birefringence. The velocities of the extraordinary and ordinary rays through the birefringent materials vary inversely with their refractive indices. The difference in velocities gives rise to a phase difference when the two beams recombine. In the case of an incident linearly polarized beam this is given by a=2pi*d(ne-no)/l (a-phase difference; d-thickness of waveplate; ne,no-refractive indices of extraordinary and ordinary rays respectively; l-wavelength). At any specific wavelength the phase difference is governed by the thickness of the retarder. Transmission range:330nm-2100nm Thermal Expansion Coefficient:7.5x10-6/K .Density:2.51g/cm3 Half Waveplate The thickness of a half waveplate is such that the phase difference is l/2-wavelength (true-zero order) or some multiple of l/2-wavelength (multiple order). A linearly polarized beam incident on a half waveplate emerges as a linearly polarized beam but rotates such that its angle to the optical axis is twice that of the incident beam. Therefore, half waveplates can be used as continuously adjustable polarization rotators. Half waveplates are used in rotating the plane of polarization, electro-optic modulation and as a variable ratio beamsplitter when used in conjunction with a polarization cube. Quarter Waveplate The thickness of the quarter waveplate is such that the phase difference is l/4 wavelength (true-zero order) or some multiple of l/4 wavelength (multiple order). If the angle q (between the electric field vector of the incident linearly polarized beam and the retarder principal plane) of the quarter waveplate is 45, the emergent beam is circularly polarized. When a quarter waveplate is double passed, i.e. by mirror reflection, it acts as a half waveplate and rotates the plane of polarization to a certain angle. Quarter waveplates are used in creating circular polarization from linear or linear polarization from circular, ellipsometry, optical pumping, suppressing unwanted reflection and optical isolation. Optically Contacted Zero-Order Waveplate • Optically Contacted • Thickness 1.5~2mm • Double Retardation Plates • Broad Spectral Bandwidth • Wide Temp. bandwidth Specifications: Material: Optical grade Crystal Quartz Dimension Tolerance: +0.0,-0.2mm Wavefront Distortion: <l/8@633nm Retardation Tolerance: <l/300 Surface Quality: 20/10 Scratch and Dig AR Coating: R<0.2% at center wavelength Standard wavelength: 532nm, 632.8nm, 800nm, 850nm, 980nm, 1064nm, 1310nm, 1550nm Cemented Zero-Order Waveplate Cemented by Epoxy Better Temperature Bandwidth Wide Wavelength Bandwidth AR Coated, R<0.2% Specifications: Material: Optical grade Crystal Quartz Dimension Tolerance: +0.0,-0.2mm Wavefront Distortion: <l/8@633nm Retardation Tolerance: <l/500 Surface Quality: 20/10 Scratch and Dig AR Coating: R<0.2% at center wavelength Standard wavelength: 266nm, 355nm, 532nm, 632.8nm, 800nm, 850nm, 980nm, 1064nm, 1310nm, 1550nm Air Spaced Zero-Order Waveplate Double Retardation Plates AR Coated,R<0.2% and Mounted High Damage Threshold Better Temperature Bandwidth Wide Wavelength Bandwidth Specifications: Material: Optical grade Crystal Quartz Dimension Tolerance: +0.0,-0.2mm Wavefront Distortion: <l/8@633nm Retardation Tolerance: <l/300 Surface Quality: 20/10 Scratch and Dig AR Coating: R<0.2% at center wavelength Standard wavelength: 266nm, 355nm, 532nm, 632.8nm, 800nm, 850nm, 980nm, 1064nm, 1310nm, 1550nm Single Plate Ture Zero-order Waveplate 1.Broad Spectral Bandwidth 2.Wide Temperature .Bandwidth 3.Wide Angle Bandwidth 4.High Damage Threshold Specifications: Material: Optical grade Crystal Quartz Dimension Tolerance: +0.0,-0.2mm Wavefront Distortion: <l/8@633nm Retardation Tolerance: <l/500 Surface Quality: 20/10 Scratch and Dig AR Coating: R<0.2% at center wavelength Standard wavelength: 1310nm, 1550nm Cemented Ture Zero-Order Waveplate Cemented by Epoxy Wide Angle Acceptance Better Temperature Bandwidth Wide Wavelength Bandwidth Specifications: Material: Optical grade Crystal Quartz Dimension Tolerance: +0.0,-0.2mm Wavefront Distortion: <l/8@633nm Retardation Tolerance: <l/500 Surface Quality: 20/10 Scratch and Dig AR Coating: R<0.2% at center wavelength Standard wavelength: 532nm, 632.8nm, 800nm, 850nm, 980nm, 1064nm, 1310nm, 1550nm Cemented Achromatic： Achromatic waveplate is similar to Zero-order waveplate except that the two plates are made from different materials, such as crystal quartz and magnesium fluoride. Since the dispersion of the birefringence can be different for the two materials, it is possible to specify the retardation values at a wavelength range. Material: Optical grade Crystal Quartz and MgF2 Dimension Tolerance: +0.0, -0.2mm Wavefront Distortion: < l/ 8@633nm Retardation Tolerance: <l/ 100 Surface Quality: 20/10 Scratch and Dig AR Coating: R<0.2% at center wavele...
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