All Questions
Tagged with optics optical-materials
157
questions
1
vote
1
answer
57
views
Why are things reflective, absorbent, transparent etc? [duplicate]
What determines whether a material reflects, absorbs or transmits a certain wavelength of light? Just a layman's question.
- 111
2
votes
2
answers
237
views
Why does light either get reflected, absorbed, or passes through a surface or obstacle?
For each of these 3 cases, I'm having trouble understanding...
If light is reflected, does that mean that there was not sufficient energy by the photons to excite the electrons of the surface to ...
- 195
2
votes
1
answer
43
views
Why does (oxidized) aluminum have a diffuse optical appearance?
Unoxidized aluminum has a shiny appearance like typical metals. However in air aluminum rapidly oxidizes, giving it a more diffuse appearance (or bidirectional reflectance distribution function). ...
- 143
1
vote
1
answer
118
views
What difference between metallic reflection and polished/mirror reflection [closed]
At the moment I am studying materials in raytracing (I am writing my own personal project)
I found out that there are several types of reflections.
I read this article from wikipedia:
https://en....
- 11
1
vote
1
answer
44
views
Are there everyday materials that change color, depending on illumination spectrum?
Initially I wanted to ask this exact question about color change due to "white" light source spectrum change, and the accepted answer satisfies me fully.
However the answer says that most of ...
- 3,034
0
votes
2
answers
156
views
Why do non-linear optical effects occur?
Why do non-linear optical effects occur? Why do the materials respond differently at high intensities and at some resonant frequencies?
- 71
1
vote
1
answer
147
views
Difference between seed and pump in chirped pulse amplifier
What is the difference between to seed an optical amplifier (such as Chirped Pulse Amplifier) and to pump it with a laser source?
- 35
3
votes
2
answers
365
views
Ideal surface for a perfect lens
in this physics lecture, on slide 15-16, it is found that the ideal surface for a perfect lens (which maps a plane wavefront into a perfect spherical wavefront, i.e. which makes focus all input ...
- 1,319
3
votes
1
answer
462
views
Brewster's angle for Metal?
As metal has a high refraction index, it is possible to have Brewster's Angle for Metal when the light incident from the air? Is it possible to derive from any formula?
- 41
0
votes
0
answers
413
views
What are good materials to diffuse/scatter 850nm infrared light?
I want to properly light up a room with an IR Illuminator, but most illuminators lack diffusion, therefore shadows are especially sharp and bold. Since IR rays don't behave like visible light rays, it'...
- 1
1
vote
1
answer
121
views
Why do efficient blue emitters (LEDs,OLEDs, quantum dots) take much longer to discover than red and green emitters?
For example, it took over 3 decades to create efficient blue LEDs in the lab after the red and green leds were discovered. For OLED displays as well, the red and green pixels are phosphorescent oleds ...
- 11
1
vote
1
answer
215
views
How does reflectance change with wavelength? [duplicate]
Sorry if this is an easy question, I am new to physics and this field.
I have a question about reflectance which i believe to be "effectiveness of reflecting radiating energy"
My goal is to ...
- 11
0
votes
1
answer
65
views
Why do some anti-reflective (or anti-glare) lenses use layers of materials with alternately very high and very low refractive indices?
Some specials lenses like this (or coatings on them) try to minimize the refractive index, or the change thereof, or at least make the change very gradual.
But others apparently do the exact opposite, ...
- 4,509
0
votes
1
answer
59
views
What formalism is used to model thin film optical coatings that function across a range of angles of incident light?
Thin film optical coatings [0] are atomically/molecularly thin layers of material applied to a substrate with the intent of affecting the optical properties of the substrate. For example, magnesium ...
- 21
0
votes
0
answers
35
views
How to get rid of unnecessary signal in Photoluminescence Spectroscopy?
I am having some issues figuring out have to get rid of laser residues (might be) or scattering from the setup itself (please see attached pic).
In the lab, we have AUREA PIXEA 405nm laser, Horiba ...
