Thanks for the video. I feel you should add some warnings to your work. I do have some larger ones and they are scary strong. If you put your hand at focal you'll get hurt, if you leave it outside you risk unintentionally starting a fire. These should be stored inside, in the dark or covered. They are not toys, but are truly wonderful devices that have yet to be fully utilized. So do enjoy them but with caution. Birds have flow through the beam and been injured or killed on larger plants. In San Luis Obispo California at the public library is an old glass lighthouse fresnel lens. Again thanks for the video.
Groves should face the sun. Since it is a flat lens, spherical aberration correction can be done on only one side. They chose the grooved side because it is easier to adjust and gives more precise results i.e. more rays converge at focus.
Thanks for the video. I feel you should add some warnings to your work. I do have some larger ones and they are scary strong. If you put your hand at focal you'll get hurt, if you leave it outside you risk unintentionally starting a fire. These should be stored inside, in the dark or covered. They are not toys, but are truly wonderful devices that have yet to be fully utilized. So do enjoy them but with caution. Birds have flow through the beam and been injured or killed on larger plants. In San Luis Obispo California at the public library is an old glass lighthouse fresnel lens. Again thanks for the video.
Thanks for your comment and safety warnings.
This is interesting.
Groves should face the sun. Since it is a flat lens, spherical aberration correction can be done on only one side. They chose the grooved side because it is easier to adjust and gives more precise results i.e. more rays converge at focus.
Thanks for watching and your comment.