The true zero order waveplate means that the thickness of waveplate is very thin (less than 0.1mm) which make the true zero order waveplate excellent in temperature, wavelength and incident angle (about 20) bandwidth. Therefore, it is excellent choice for the highly accurate application. It is cemented with a block of glass which is limited to low and medium power application. Key features: - broad spectral bandwidth - wide temperature bandwidth - wide angle bandwidth - cemented by epoxy Technical capability Material: Crystal quartz / bk7 optical glass Dimension tolerance: +0.0, -0.1mm Wavefront distortion: 8 @ 632.8nm Retardation tolerance: 500 Wavelength range: 400-2100nm Parallelism: < 1 arc second Surface quality: 20-10 scratch & dig Coating: Ar/ar coating, r < 0.2% on both surface at central wavelength