The invention relates to a refractive surface for blocking short- and medium-wavelength visible-spectrum radiation that affects human physiology. The refractive surface selectively absorbs short wavelengths between 380 nm and 500 nm, between a maximum and a minimum absorption threshold, and selectively absorbs medium wavelengths between 500 nm and 590 nm, between a maximum and a minimum absorption threshold, the selective absorption of short and medium wavelengths between 380 nm and 590 nm not completely blocking the passage of visible light in this range. Other embodiments include an LED screen, a software product and an electronic device, and ophthalmic, intraocular or sunglass lenses.

The present application relates to a welding helmet comprising a helmet housing and a head cover adapted to be worn on a wearer's head and made of an air-impermeable and flexible material, wherein a zipper arrangement is provided between the helmet housing and the head cover to detachably connect the head cover to the helmet housing around the whole perimeter of an opening of the helmet housing, and wherein after the head cover is connected to the helmet housing, the zipper arrangement is located within the housing of the welding helmet. The present application also relates to an assembly having the welding helmet.

Protective headgear including an automatic darkening filter with an array of switchable shutters, and including a shutter control system, at least one workview image acquisition device, and at least one eye position monitoring device, wherein the shutter control system is controllably connected to each switchable shutter of the array of switchable shutters so as to control the switching of each of the switchable shutters, and is receivably connected to the at least one workview image acquisition device and to the at least one eye position monitoring device.

An improved personal protective device and composition thereof. The device comprises arc flash spectacles or goggles, an arc flash faceshield or an arc flash hood window to provide optical clarity, specifically color acuity. The spectacles or goggles, the faceshield and the hood window include polycarbonate material for high-impact, high-mass performance, and surface charring during arc flash exposure and provides an arc flash protective rating of at least 4 cal/cm.sup.2 (in the case of eyewear and face shields) or at least 15 cal/cm.sup.2 (in the case of hood windows).

A vision-protecting filter lens, including a multilayer optical film and a neutral-density optical filter.

An improved personal protective device and composition thereof. The device comprises arc flash spectacles or goggles, an arc flash faceshield or an arc flash hood window to provide optical clarity, specifically color acuity. The spectacles or goggles, the faceshield and the hood window include polycarbonate material for high-impact, high-mass performance, and surface charring during arc flash exposure and provides an arc flash protective rating of at least 4 cal/cm.sup.2 (in the case of eyewear and face shields) or at least 15 cal/cm.sup.2 (in the case of hood windows).

An optically transparent device includes an exterior lens and an optical filter coupled to an inner surface of the exterior lens. A protective coating comprised of an acrylate may be coupled to an inner surface of the optical filter to reduce fragments of the optical filter from detaching from the exterior lens.

A welding hood for protecting an operator's face comprising a face protective shield having a concave rearward side for receiving the operator's face, a viewing opening extending through the shield, wherein the viewing opening is located in a position in front of the eyes of the operator while the hood is fixed to the operator's head. The welding hood includes an eye box located adjacent the viewing opening. The eye box has walls framing the viewing opening and extend inwardly from the rearward side of the shield. The walls are configured for blocking reflective arc flashes and/or light from entering the operator's field of view during welding. The welding hood has sidewalls of varying width and a neck attachment for added protection. The welding hood also includes a lens located within the viewing opening and at least one strap for securing the welding hood to the operator's head.

A personal powered air respirator, for example a welding or spraying helmet (10), includes a remote controller (30) for adjusting one or more operating parameters of the helmet and a means of displaying information regarding said parameter in, on or adjacent the interior of the vision panel (12) of the helmet. The invention allows for convenient adjustment in use. The remote controller is adapted to clothing, such as belt, glove or pocket, or may be incorporated in equipment for use with the helmet.

A method of forming a filter, comprising the steps of: selecting at least a first wavelength corresponding to a predetermined laser threat and having a first colour in the visible spectrum; providing a generally transparent substrate and forming a first notch filter region therein configured to substantially block incident radiation thereon of wavelengths within a first predetermined wavelength band including said first wavelength; selecting a second wavelength having a second colour in the visible spectrum and forming a colour balancing notch filter region in said substrate configured to block incident radiation thereon of wavelengths within a wavelength band including said second wavelength, thereby to balance or neutralise any colour distortion of said substrate caused by said first notch filter region.