These data are measured, so there is likely some experimental bias responsible for the discrepancy. When pulse lengths are between 1 ns and 1 µs, laser-induced damage can occur either because of absorption or a dielectric breakdown (therefore, a user must check both CW and pulsed LIDT). Thank you for your feedback. Damage threshold specifications are constant for a given coating type, regardless of the size and shape of the mirror. Thanks. In an instrument we are going to use broadband mirrors 540 nm to 900 nm at nominal an AOI of 45 degrees. We have contacted you with the GVD data. Thank you. Feel free to reply to that if you would like to discuss it with me. After exposure, the optic is examined by a microscope (~100X magnification) for any visible damage. See Figure 1 as an example. Thorlabs' LIDT testing is done in compliance with ISO/DIS 11254 and ISO 21254 specifications.First, a low-power/energy beam is directed to the optic under test. Hello! Thank you for your comments on this page. Thorlabs' Fused Silica Broadband Dielectric Mirrors offer excellent reflectance over four different spectral ranges. ( the mirror has a single reflection peak when used from one end, but it is transparent (zero reflection) when used from the Response from Tim at Thorlabs to John: Thank you for contacting us. Phase shift due to reflection. Good day, I want to use mirror to reflect HeNe laser placed in a set-up in which oscillating magnetic field in the kHz to MHz frequency is present. Wide selection of dielectric and metallic mirrors from stock. Custom mirrors can be requested by emailing techsupport@thorlabs.com. The pulsed LIDT of the optic is significantly greater than the energy density of the laser pulse, so individual pulses will not damage the wave plate. It makes sense to me to include both. The typical substrates that we use have surface flatness of ?/10. right-handed circularly polarized light changes to left-handed circularly polarized light and vice versa.) The shaded region in each graph denotes the spectral range over which the coating is highly reflective. While the test results are only representative of one coating run, Thorlabs specifies damage threshold values that account for coating variances. This diameter provides a larger clear aperture than Ø1/2" optics while allowing the mounts to maintain a Ø1" footprint. This is the same principle used in multi-layer anti-reflection coatings, which are dielectric stacks which have been designed to minimize rather than maximize reflectivity. At 45 degrees. Polymeric dielectric mirrors are fabricated industrially via co-hextrusion of melt polymers,[2] and by spin-coating[3] or dip-coating[4] on smaller scale. 1000- 1200. Tian Seng. This is the same principle used in multi-layer anti-reflection coatings, which are dielectric stacks which have been designed to minimize rather than maximize reflectivity. with extremely broad reflection bands. In response to acables post, we have added the thickness for these mirrors to the specs tab. For applications that require a mirror that bridges the spectral range between two dielectric coatings, please consider a metallic mirror. opposite end) When an optic is damaged by a continuous wave (CW) laser, it is usually due to the melting of the surface as a result of absorbing the laser's energy or damage to the optical coating (antireflection) [1]. Rev. Can you give information on the phase shift in the E02 coating between s- and p-polarized light (for a wavelength of 532 nm and an angle of incidence of 45 degree)? Can I use dielectric mirror with this? This calculator assumes a Gaussian beam profile, so a correction factor must be introduced for other beam shapes (uniform, etc.). (See also our privacy declaration.) 1. By careful choice of the type and thickness of the dielectric layers, one can design an optical coating with specified reflectivity at different wavelengths of light.