Ultrafast laser systems are becoming more widespread throughout the research and industrial communities, yet eye protection for these high power, bright pulsed sources still requires scrupulous characterization and testing before use. Femtosecond lasers, with pulses naturally possessing a broad-bandwidth and high average power with a variable repetition rate, can exhibit spectral side-bands and subtly changing center wavelengths, which may unknowingly affect eyewear safety protection. Pulse spectral characterization and power diagnostics are presented for a 80 MHz, Ti+3:Sapphire, ≈800 nm, and ≈40 fs oscillator system. Power and spectral transmission for 22 test samples are measured to determine whether they fall within manufacturer specifications.

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See https://www.lia.org/evaluator/od.php for free use of the calculator.
8.
Certain commercial equipment or materials are identified in this paper to adequately specify the experimental procedures. In no case does the identification imply recommendation or endorsement by NIST, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.
9.
See supplementary material at http://dx.doi.org/10.2351/1.5004090 for Fig. S1: Beam profiles (image and x, y cuts) with extracted diameters (FWHM in mm) obtained by using a 1216 × 1936 pixel CMOS camera at sample positions with beam diameters of ca. 2 and 10 mm. Figure S2: Description of employed laboratory eyewear with vendor specifications, measured OD values, and spectra at various laser center wavelengths. Figure S3: Similar descriptions for test sample N.

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