Kenko Tokina stargazing glasses reduce light pollution

Kenko Tokina has unveiled Asterism Glasses, eyeglasses designed to improve the ability to view the stars at night. The pair is priced at 17,600 yen (~$120) and is available for purchase on the company's website in Japan.

Many city dwellers are unable to see the stars clearly, or even at all, at night due to light pollution. Street lights, car headlamps, external landscape lights, lighted signs, and other sources of light at night produce an atmospheric glow that hinders the ability to see the stars. The extent of this can be viewed in this online light pollution map of the world.

Much of the light comes from street lamps, which often use mercury-vapor or sodium-vapor bulbs that have strong emissions centered around the 450 nm (blueish) and 600 nm (yellowish) wavelengths. The Asterism Glasses use flexible thermoplastic lenses (TR-90) coated to reduce light in these areas. The lenses also have an AR coating to reduce unwanted reflections from nearby light sources.

The lenses incorporate Itoh Optical Industrial's ES extended depth-of-field lens technology, a permanent focus accommodation to optimize viewing of distant stars. Because of this focus adjustment in the lens, they are registered as medical devices in Japan.

The Asterism Glasses measure 160 × 50 × 175 mm (6.30 x 1.97 x 6.89 in.) and weigh 33 g (1.16 oz). They can be worn over prescription eyeglasses.

Readers with telescopes can buy light filters like these on Amazon to reduce the effect of light pollution.