DIY Sunglasses

Safety Note 

Always protect yourself from the sun when working outdoors. NEVER look directly into the sun, unless you are wearing special sunglasses made for that purpose (so called “solar viewers”).

Use scissors and glue with care to avoid accidents. Do not let younger kids use a utility knife.

Activity Guide:

1. Print or copy the template provided on thick paper or cardboard. NOTE: There are two versions of the template. The one with 100% is for youth and adults, while the one with 90% is for kids. What makes the difference? The distance between the eyes becomes bigger as you grow up.
2. Carefully cut out the silhouette of all parts of the sunglassess. 
3. Use scissors to cut out the squares in the central part, where the glasses will be placed.
4. Glue pieces of tinted or polarised film on the inside of the central part, aligning them with the cut out squares.
5. Fold the central part along the long side, forming the frame of the sunglasses.
6. Fold the left and right extremes of the central part to attach the sunglasses' earpieces. 
7. Attach the side parts with a clip (adjusting until you find the size which fits you best).
8. Glue the side parts to the center part, unless you want to keep the sunglasses adjustable. 
9. Optional: Paint and decorate your sunglasses to make them unique and stylish.

Exploring how Sunglasses work. 

Sunglasses protect the eye from different factors which may harm it:

• Ultraviolet (UV) light
• Excess intensity of visible light

Optionally:

• Blue light
• Glare from reflective surfaces

Ultraviolet light (UV) is harmful for the skin and even much more for the eye. It is important that sunglasses filter the UV part of the light and reduce its intensity by minimum 99%. The quality of UV protection cannot be judged with our eyes, only analytical equipment can test that.

Even the visible part of the light (i.e. “all the colours” without ultraviolet and infrared light) can harm the eye if the intensity is high, for instance in the mountains with snow reflecting sunlight or at the sea where the water reflects the light. Sunglasses must reduce the intensity of the light from 20% (very little protection) up to 97% (very strong protection, to be used on glaciers, for instance). The factor of reduction can be judged by its “blackness”. Be aware that even the strongest regular sunglasses are not made for looking directly at the sun! To see an eclipse, only special “solar viewers” can be used.

Even blue light might have a negative impact on our health. Some glasses serve to (partly) filter the blue light. They might be used for long work at computer screens.

If we are outdoors close to water or snow (“shiny non-metallic surfaces”), the reflection of the sunlight can affect our vision. There are special glasses, called “polaroid”, which can reduce the discomfort of glare. They are especially useful for fishermen

Reflection Questions

 1. What are the factors that make a stay in the high mountains more dangerous for our eyes?

2. Why do we need very strong sunglasses if we try to ignite a bit of wood using sunlight and a lens?

3. Why are dark glasses without UV protection even worse for the eyes than not using sunglasses?
 

Additional Activities

Experiment with different tinting options by adjusting the number of tinted film layers. If your glasses will be used with very strong light (bright spot of sunlight concentrated by a lens), use more than one layer of the film to get very strong protection.

If your film is polarized, experiment with two layers: twist slowly one layer as compared to the other one. Compare the intensity of light passing and discuss the effects of polarization on light transmission. (Be aware: Some films sold as “polarized” are actually not polarized. If the experiment doesn’t work, this is probably the case of your sample of film.)

The provided sunglasses template ensures accuracy and facilitates easy assembly for participants. Choose the 90% size template for kids under 10 years and the 100% size template for older kids and adults.

Background information:

The Sun: Benefits and Risks

The sun plays several vital roles in our lives, such as maintaining a comfortable temperature, producing vitamin D, and contributing to improved mental health by combating issues like depression. However, knowing the potential dangers of the sun's ultraviolet (UV) rays is essential.

UV rays adversely affect not only our eyes, but also our skin, leading to premature ageing and impacting even the deepest layers. Sun exposure can cause temporary or permanent damage, like sunburn and, in severe cases, skin cancer. Directly looking into the sun through a lens or mirror can impair vision or cause blindness. Excessive time spent in the sun without proper precautions may lead to sunstroke, which can be a medical emergency.

Different skin types offer varying levels of protection against the sun. Tanned or dark skin provides slightly better protection than lighter skin. While sunscreen enhances the skin's self-protection, it is crucial to recognize that sunburn or skin cancer may still occur for all skin types depending on the Sun Protection Factor (SPF).

To prevent sunstroke, stay hydrated by drinking enough water, seek shade whenever possible, avoid being outdoors during the hottest hours (11 am to 3 pm), and wear a hat that provides shade for the face, neck, and ears.

As you engage in outdoor activities, remember to balance enjoying the sun's benefits and taking necessary precautions to safeguard your skin and overall well-being.