I like to share the little magical-feeling things I had as a kid with the kids in my life. This is the perfect way to share diffraction lenses as part of Christmas gifts and for Halloween trick or treat bags.
Don't get these if you like seeing people smile and making friends, because these are a huge hit. Super fun.
Many years ago at an EDM concert, someone gave one of these to my wife and me. Since then, we have bought thousands of them and given them away ourselves. Everyone loves them. It goes the same way every time. We hand it to a stranger, they look at it and go, "Huh? Wha?" Then we show them - look at the lasers through the disc (we call them laser discs). The person looks through the laser disc at the lasers and the stage, and they go "WHOA!" and they thank us a million times, and then they show it to their partner or friend, and we give one to that person too. Same reaction. We love it!
Rainbow Symphony's diffraction grating rainbow peepholes are used in our science workshop exploring light. Compact and effective, students explore dispersion of light with their peepholes.
They are wonderful. I have been using them for decades, usually buying around 500 or so per year. I give them to kids, people who have helped me, as part of tips at restaurants and stores, to school kids who visited our science department at the university where I used to teach (before retirement), as part of children's messages at my church, and as Christmas gifts to kids, especially relatives. I almost always have some with me wherever I go. The vast majority of people to whom I give them seem to really like them.
