Solar viewer

Solar viewer refers to a device or material used to safely observe the Sun or solar eclipses. Observing the Sun without proper protection can lead to serious and permanent eye damage, including blindness. Therefore, solar viewers are designed to filter out a significant portion of the Sun's harmful rays, allowing individuals to look at the Sun directly without causing harm to their eyes.

Types of Solar Viewers

There are several types of solar viewers, each employing different methods to protect the eyes from the Sun's harmful radiation.

Eclipse Glasses

Eclipse glasses are the most common type of solar viewer. They are made of a special solar filter material that blocks out 99.999% of visible light and harmful solar radiation. These glasses should meet the ISO 12312-2 international safety standard to ensure adequate eye protection.

Solar Telescopes

Solar telescopes are specialized telescopes equipped with filters to reduce the intensity of sunlight to safe levels. These telescopes often use a hydrogen-alpha filter to observe the Sun in a narrow wavelength, highlighting features such as solar flares and prominences.

Pinhole Projectors

Pinhole projectors are a simple, indirect method for observing solar eclipses. They do not require looking at the Sun directly. Instead, a pinhole in a card projects an image of the Sun onto a second surface, allowing safe observation of the Sun's shape and any ongoing eclipses.

Welder's Glass

Welder's glass of Shade 14 or darker can be used as a solar viewer. It is important to ensure that the welder's glass is sufficiently dark to safely observe the Sun without risking eye damage.

Safety Considerations

When using solar viewers, it is crucial to inspect them for any damage, such as scratches or tears, before each use. Damaged viewers should not be used as they may not adequately protect the eyes. Additionally, when observing a solar eclipse, it is unsafe to look at the Sun directly without protection at any time, except during the brief total phase of a total solar eclipse, when the Sun's bright face is completely covered by the Moon.

Conclusion

Solar viewers are essential for safely observing the Sun and solar eclipses. Whether using eclipse glasses, solar telescopes, pinhole projectors, or welder's glass, it is vital to ensure that the method of observation meets safety standards to protect the eyes from permanent damage.