Some questions about light and vision.

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The discussion centers on the human eye's ability to detect light, questioning how few photons can be perceived and the necessary conditions for visibility. It explores the concept of creating materials that can project light omnidirectionally, potentially allowing for screens that offer different images from various angles, similar to mirrors or windows. Additionally, it considers the feasibility of storing visible light and projecting it later, as well as the idea of a mirror-like object that reflects light after a delay. Participants seek guidance on researching these topics further, indicating a need for clarity on the physics involved. The conversation highlights the intersection of light perception and innovative material science.
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1) How powerful is the human eye at discerning differences in light? (in a completely dark room could you make out one photon, how much light needs to emanate from a single point to be visable, how close of an angle must separate beams of light be projected in order to appear seamless to the eye?)

2) Since objects reflect light in all directions, then theoretically could a material be created that projects light in all directions? (instead of projecting light onto a screen at a movie, and then seeing the same flat image from all angles, could you have a screen that projects slightly differently at each angle and thus create the same illusion as a mirror, or the appearance of a window?)

3) As relating to question 2, could visible light be stored and then projected again? (for example, a dull black surface while recording light, the appearance of a mirror while releasing that light)

4) As relating to question 3, could a mirror-like object be made that reflects its light after a duration? (a delayed mirror whether by a few seconds or a few hours)

Answer any or all of these questions, after reading them you can see the general ideas so work off of those.
 
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Welcome to PF GPMann. Please note that you are required to show your attempts at homework questions before we can help you.
 
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EDIT: explanation removed. Didnt realize that this was moved to the homework section. Sorry.
 
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Sorry, I didn't mean to post it in the homework thread, how do I put it in a genera physics section?
 
GPMann said:
Sorry, I didn't mean to post it in the homework thread, how do I put it in a genera physics section?

You did put in the general physics section, but it was moved because it looked like a homework problem.
 
Can anyone at least point me in the right direction for where to research these topics?
 
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