Today we discuss a seasonal Halacha for the summer months. The question was asked, whether or not it is permissible to wear sunglasses on Shabbat whose lenses change color as it gets exposed to the sun. There are certain types of lenses that are clear while indoors, but when moving outdoors it automatically tints and darkens. These lenses adjust and actually convert into sunglasses when going outside, and then back again to clear when returning indoors.
Why is the question asked? One of the 39 Melachot prohibited on Shabbat is called Sovea. Sovea means dying. You are not allowed to paint things, and color things, and dye things on Shabbat. So the question regarding the sunglasses is asked because technically you are causing the lenses to become colored and clear as you move from indoors to outdoors and back.
Chacham Ovadia discusses this question in several places. He discusses this in Halichot Olam and also in Yechave Da’at. He holds Halacha Lema’ase, without going into the whole story, that it is permissible. Basically his reason is based on the fact the color changing lenses is not from the normal way to make Sovea. He holds that it is permissible to wear such glasses because the color changing is happening due to the sun, and it is not the normal way.
I want to just review the basic Halacha of whether or not you may wear sunglasses on Shabbat where there is no Eruv. Chacham Ovadia rules that it is permissible on a sunny day for a person to wear sun glasses because he needs them. We do not suspect that he might take them off and come to carry them. Therefore, those who want to wear sunglasses on Shabbat, they definitely have what to rely on, even in a place where there is no Eruv.