Laser attenuation device with sacrificial mirror

An eye protection device adapted to protect against a broad spectrum of incident high intensity radiation while allowing the transmission of normal radiation levels, including:

• a beam splitter which transmits a substantial portion of the incident radiation beam;
• a focusing lens placed on the side of the beam splitter opposite the source of the incident radiation beam, the lens receiving and focusing the incident radiation beam to a narrowly defined focusing area to further intensify the incident radiation beam;
• a first mirror placed and adapted to receive the focused incident radiation from the first lens, the surface of the mirror being sufficiently absorptive of incident radiation that a focused incident beam with an initial intensity of at least 25 millijoules will cause a heating of the mirror surface to the vaporization temperature of the reflective surface of the mirror at the point of the focused beam;
• a second lens placed to receive radiation reflected from the first mirror and recollimates the light onto a reflective surface of a second mirror the recollimated beam reflecting off the second mirror is then reflected back through the second lens which refocuses the beam onto the sacrificial surface of the first mirror at the area originally heated by the beam, if the initial beam was above the threshold, the reflectivity of the surface at this location will have been destroyed by the initial heating of the beam and the beam will pass through the mirror but if the beam was not sufficient to destroy the surface, the beam will be reflected off the first mirror, through the first lens and onto and the side of the beam splitter facing the first lens which passes the beam to the receiving device.