Engineering Stack Exchange
Engineering Stack Exchange

Questions tagged [optics]

Optics is a branch of physics describing the behaviors and properties of light (electromagnetic waves). Questions regarding the properties of light, it's interactions with matter and the instruments used to detect and deflect (or concentrate) light should be posted here.

Optics is a branch of physics describing the behaviors and properties of light (electromagnetic waves). Questions regarding the properties of light, it's interactions with matter and the instruments used to detect and deflect (or concentrate) light should be posted here.

Some Relevant Categories:

  • geometric optics (ray theory)
  • physical optics (diffraction & interference)
  • Quantum optics (photonic behavior)

Lenses and mirrors would apply.

179 questions
17
votes
3 answers

Why is it more reliable to use the land/pit transition in a CD-ROM?

I was reading about how CD-ROMs work and I came to this: Although it might seem simplest to use a pit to record a 0 and a land to record a 1, it is more reliable to use a pit/land or land/pit transition for a 1 and its absence as a 0,so this…
Kate
  • 173
  • 1
  • 5
14
votes
2 answers

Why are lasers used for concentrated light applications instead of incoherent light sources?

Some laser applications consist simply of concentrating light into a small spot. Two example applications are laser welding and cutting. In these cases a CO2 laser is often used which needs a regulated power supply, a water cooling system, and a…
user3368561
  • 749
  • 5
  • 11
12
votes
4 answers

Will more electricity be generated by using a lens to focus sunlight onto solar cells?

I have been wondering about this question for quite some time. Assuming an ideal case, the energy from photons hitting solar cells is converted into electric energy as described by the equation: $RI^2t=W\equiv E=\hbar\nu$ where $\nu$ is the…
TBBT
  • 223
  • 2
  • 5
11
votes
1 answer

How does a microbolometer (IR camera) work?

I am currently doing a project which has led me to my first encounter with IR cameras, and I am therefore quite curious as to how they operate. Specifically, I would like to know the following How is heat converted to an electrical signal (current…
Julian
  • 273
  • 1
  • 8
10
votes
2 answers

Can a very bright light attract an incoming laser guided weapon?

I would like to know if a very bright light will attract an incoming laser guided weapon such as a laser guided missile. Say for example that a tank has a six-foot pole on the top of it and attached to the end of this pole is a high-voltage carbon…
user33377
10
votes
1 answer

What is the focal distance of an optical mouse?

I am trying to build an optical sensor for my old school, state property, standard french watt-o-meter. EDF ( Electricité de France ) has a gig which turns a wheel depending on watt consumption. The higher the wattage, the faster a tiny disk turns.…
Martin
  • 203
  • 1
  • 5
10
votes
1 answer

What liquid crystals are used most frequently in displays?

Is there a specific chemical that is used frequently in the production of liquid crystal displays? During my internet research so far, it seems as if the specific chemical composition of the liquid crystal does not matter very much. This website…
DK2AX
  • 355
  • 3
  • 12
9
votes
4 answers

Can cameras+display screens with window/mirror-like optical behaviour exist?

Display screens connected to cameras are significantly different from windows or mirrors. Looking through a window or mirror, we can focus on infinity, and we can move our vantage point to see a little different. With a display screen showing live…
gerrit
  • 321
  • 1
  • 13
8
votes
1 answer

How can I estimate blocking window distance in an sCMOS sensor setup?

I am trying to establish an appropriate distance between a spectrograph output window and a CMOS sensor. The spectrograph creates a focused image on the CMOS sensor but I am trying to restrict the light as the initial pixels are capturing light of…
Akhil
  • 181
  • 2
7
votes
4 answers

Must rifle scopes have revealing reflections?

It's a movie trope that snipers are spotted because someone catches a glimpse of a reflection of the scope. It seems to me that this is a serious design flaw. I also know that a good number of scopes have "lids" to protect against dirt, etc., when…
KlaymenDK
  • 241
  • 2
  • 8
6
votes
4 answers

Precision measurement of liquid levels

How can I measure changes in liquid level of the order of 50 μm? The tank is cylindrical with a radius of about 12.5 mm and a total volume of about 45 ml. The fluid is water-based. The technique needs to be optical or similar because no external…
Worldsheep
  • 383
  • 1
  • 10
6
votes
1 answer

What does 'easily reversed' mean in the NIST spectral database?

I'm trying to do some processing of optical emission spectra from sputtering plasmas, and am confused by what NIST means by 'easily reversed' in their notation. Anyone have a clue?
wordsforthewise
  • 163
  • 4
6
votes
2 answers

How to avoid dyed liquids staining reflective/transparent surfaces

I'm dealing with some hydrocarbons (diesel, gas oil, kerosene, ethanol) where I'm putting them in a chamber and shining light through them to hit a sensor on the other side in order to measure their colour. Unfortunately what I'm finding is that the…
Amr Bekhit
  • 163
  • 5
6
votes
4 answers

Why aren't screens round instead of rectangular?

Screens on TVs and phones et cetera are always rectangular. Why? Why are they not round? Eyes are round. The Sun, the source of almost all of our light, is round. Telescopes have round lenses and mirrors. If a photon has a shape it would be round…
LocalFluff
  • 1,111
  • 1
  • 8
  • 8
5
votes
2 answers

Transparent, hard material that lets infrared through

I am trying to build a protective enclosure for Microsoft's Kinect v2, which emits (and perceives) IR in the 827–850 nm range. In order to fully enclose the device without blocking those signals, I need some transparent and hard material that will…
Kal
  • 151
  • 4
1
2 3
…
11 12