How does light interact with objects to create vision?

[anni]

Hi Physics friends. Quick Question at a very, very basic level regarding vision. It’s so basic that it needs to be checked out to make sure I’m distilling it properly. Can I do it like this?

“At a very basic level, we see an object because light reflects off of it and hits our eyes. The darker the object, the more light is absorbed rather than reflected back at us.”

 

[phinds]

Yes, that's correct, as a basic statement of vision.

 

[anni]

Thank you! I totally get the first part. But why do dark objects absorb more light rather than reflect it?

 

[phinds]

Thank you! I totally get the first part. But why do dark objects absorb more light rather than reflect it?

What research have you done on that? What have you found out? Which part do you not understand?

 

[anni]

I haven't done any research other than working my brain.

What I understand: We see objects because they either give off their own light, or light reflects off the objects and enters our eyes. The moon is an interesting example. It doesn’t make its own light – we can see the moon because it reflects light from the sun. If an object did not reflect any light, we would not be able to see it.

What I do not understand: Why do dark objects absorb more light? And: why rather than reflect it?

 

[hutchphd]

How many years do you wish to devote to this answer??You could learn much of physics.
One major category in your researches should be the different types of reflection...diffuse, specular, coherent , etc.
But you should spend some time with Google and then ask us the stuff you are wrestling with understanding...

 

[phinds]

I haven't done any research other than working my brain.
...
Why do dark objects absorb more light? And: why rather than reflect it?

We're not really a Q&A forum. We expect people to have made some effort on their own and come here to ask about what they don't understand from what they have found out.

 

[berkeman]

Welcome to the PF, anni!

Why do dark objects absorb more light? And: why rather than reflect it?

Just to give you a little boost in helping you to answer this question... I used Google to search on color reflection absorption and got lots of good hits. (I searched on color instead of just dark/light, because your question really is more general than just black and white light). Here is the first hit on the list:

https://www.physicsclassroom.com/class/light/Lesson-2/Light-Absorption,-Reflection,-and-Transmission
That should get you a long way toward answering your questions about vision and light. You can also do that same Google search and add other search terms into get you to other good articles about the subject. Please do post questions that you have after doing some of that reading. That is what the PF does best -- we are happy to answer questions about the reading you have been doing if you are not understanding something, or are having trouble with search terms in your studies.