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US: Laser-emitting binoculars being sold for "night vision"

Binoculars that emit a diffused green laser light onto a person or subject of interest are being sold by online and catalog retailers such as Amazon.com and Sharper Image.

The Cassini K-9 “Day and Night Vision Binoculars” are normal magnifying binoculars (for day vision) with a green laser light added between the lenses to illuminate objects for “night vision.” Holding down a button activates a 532 nanometer laser, said to be less than 5 milliwatts, with a spot diameter of 4 meters at a distance of 50 meters.

Cassini K-9 laser binocular


Looking through standard night vision devices, the user typically sees a green glow from the image intensifier that allows enhanced vision in the dark, without any visible light being added to the scene. In contrast, the Cassini K-9 emits very visible green laser light, simulating the look of a night vision device without requiring any other change to the binoculars.

The product manual warns “Please note the green laser is a device and can be harmful if used improperly, and laser radiation can be harmful to the eyes. Do not look directly into the laser beam output aperture during operation. Laser light when reflected off a mirror like surface can cause serious damage and injury. Since the Laser binocular is not a toy, please keep out of reach of children.”

The manual also includes this cautionary graphic:

Cassini K-9 laser binocular warning

Representative prices range from $94 (Amazon) to $160 (Sharper Image). At Amazon, the product has 3.5 out of 5 stars from 13 reviewers. Amazon reviewer comments include:

  • “Didn't realize it would have the bright beam of green light...Very grainy, hard to make thing out….”
  • “If you are looking for something to view the dark, without being detected, this is not the one. The green laser is visible!! That's, like you can see it in the dark! The range is not up to par. The beam is cone shaped and is approximately 2 feet wide at 7 yards, carry that out to 100 yards, my scope works better at night with my mag-light.”
  • “Much better than reviews indicated. Not for tactical use but adequate for bird watching or varmint spotting.”

From Amazon.com and Sharper Image

US: Lasers used to tag UFOs?

According to an article at Examiner.com, college students are using lasers to tag UFOs that they see using night vision equipment. Author Tom Rose, the “East Stroudsburg Paranormal Examiner,” writes that night vision equipment is now more affordable, so it can be used to detect cloaked objects in the sky. These may be secret military aircraft or extraterrestrial ships.

Rose refers to YouTube clips where handheld lasers are pointed at moving dots of light in the sky.

Click to read more...

Israel: Advanced anti-laser filter announced

A newly developed anti-laser filter works by blocking laser light based not just on the wavelength (color) as with traditional filters, but based also on the light level (irradiance). KiloLambda Technologies of Tel Aviv says their filter “is clear at all wavelengths until it is hit by an incoming power above a certain level. Below the threshold, the filter has high transmission over the whole spectral band, but when the input power exceeds the threshold, transmission is either limited to a certain value or blocked completely."

It is not clear whether the filter is available at this time (May 2012). The company intends to incorporate it into glasses and night-vision goggles worn by pilots, to protect against flash blindness, meaning power densities from 100 µW/cm² up to 1000 µW/cm².

From Optics.org

US: Tampa police purchase anti-laser filters for night vision goggles

The Tampa (Florida) Police Department Aviation Unit has purchased anti-laser filters for use with night vision goggles (NFGs). Manufacturer Night Flight Concepts said that Tampa is one of the first law enforcement agencies to use the filters. According to Aviation Today, the Tampa police department has four helicopters: two Bell 407s, one Bell 206, and a Hughes OH-6.

A person wearing NVGs is normally not at risk of retinal injuries, since direct laser light falls on the image intensifier device and not the eyes. (Depending on the NVG mounting style, it may be possible for direct laser light to enter from the side or from parts of the vision not covered by the NVG optics.) However, a serious concern is with laser light causing “blooming” of the night vision enhanced image, or even damaging the NVG sensor. To help prevent this, Night Flight Concepts developed “Laser Armor” Light Interference Filters.

Pic 2012-03-01 at 11.51.53 AM


Company consultant Dr. Dudley Crosson says the screw-in filters “allow the goggles to function normally by reducing the blooming effect significantly.” A Laser Armor product sheet says the filters reduce blue (445-450 nm) intensity by 97%, and reduce green (532 nm) intensity by 99.5%.

From Aviation Today and a Night Flight Concepts press release