Questions tagged [photonics]
The photonics tag has no usage guidance.
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Can air be implemented in 1-Dimensional photonic crystals?
As far as I am aware, digging holes in nanostructures or using columns of materials in a medium of air is the main way by which 2D photonic crystals work. I thought it would also be common to ...
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What causes phase walk-off reversal in inverted domains in Quasi-Phase-Matching?
Lets take for example a Periodically Poled Lithium Niobate crystal (PPLN) used in a nonlinear process such as Second Harmonic Generation (SHG). For this crystal, the purpose of periodic poling is to ...
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Where can I get a 4.26µm wavelength light source with variable intensity?
I want to conduct a small home experiment involving co2 particles detection.
In order to do that I need a light source at 4.26µm wavelength (it's absorbed by co2 molecules), preferably with ...
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AutoCAD: Help with exporting micrometer details to PDF
I'm using AutoCAD and am trying to export a photolithography mask to a PDF file so it can be viewed and shown to others outside of the AutoCAD program. I'm having trouble with this, as whenever I ...
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Imaging base of HDR range
When speaking about HDR photography, do the magnitudes are measured in base 2 (stops) or base 10 (decibel)?
I mean - what is the magnitude in linear scale of, for example, 100 dB HDR?
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How is light guided by a perfect mirror waveguide for angles not exactly at the guided mode angles?
Take the below image for example:
Let's imagine the cladding is really just perfect mirrors, where all light energy is reflected back towards the core. I understand that modes arise by imposing the ...
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Calculating Temperature of an Optical Fiber
Let's say there is 30W of light pumping into the fiber.
Parameters:
Length of Fiber: 6cm
Input - 30 W
Output -29W
Loss of 1W
The diameter of optical fiber is 0.25mm.
Since the optical fiber is ...
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Heat loss in Optical Fiber
I am conducting a thermal analysis of optical fibers. ( Software used AutoCAD Fusion 360)
The Inputs conditions are :
Let's assume an input power of 1250W, with an efficiency of 98%. 2% loss which ...
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Comparison of beam divergence between laser diode and DPSS laser
I'm currently comparing a pulsed laser diode and a pulsed DPSS laser. For the DPSS laser, the beam divergence is listed as "beam divergence (80% of total energy): $<4 \text{mr}$". The ...
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Calculate the temperature stability of wavelength demultiplexer
Hi ive been given this question:
A wavelength demultiplexer (DMUX) used in a DWDM communication system has a
channel spacing of 100 GHz. The operating pass band of each channel is 50 GHz. The
...
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What are some examples of laser-based additive manufacturing techniques?
I'm trying to research additive (or 'bottom-up') fabrication techniques that rely on lasers or other advanced photonic systems. So far, the most prevalent technique I've come across is two-photon ...
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How would measuring the number of photons on a finite number of pulses break coherence of a weak coherent laser source in COW QKD protocol
I' m trying to understand attacks on Quantum key distribution protocols. In the COW QKD protocol, pulses from Alice are passed through an asymmetric
coupler and a fraction 'T' of the photons are sent ...
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LED Lumen Calculations
I am using an LED as a point source for a school project. I have two questions in regards to the LED(s).
I know that light follows the inverse square law when measuring perceived brightness, but all ...
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Epoxy that can withstand up to 800C and is optically transparent?
I'm looking to use an epoxy in a high-temp environment like 800C, and one that is optically transparent at 450nm (not below 90% transmission). But i'm having trouble finding one. It can be made of any ...
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galvo scanner + rotating off-axis mirror for beam offseting?
diagram:
Assuming
1) the scanner can angle a beam anywhere on the circular off-axis mirror and
2) the off-axis mirror can be rotated as an the diagram to any angle needed,
can the beam shooting ...
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rotating mirror system for shifting a beam?
I am looking for some mirror setup where rotation one or more elements in the mirror setup will allow to shift the beam along its axis.
Two mirrors in a galvanometer scanner type setup work well for ...
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how to implement autofocus for video projector
I have a modified pico video projector that I need to add an autofocus to.
The focusing ring already has a fast stepper motor added to it.
If the focus had to be done on the middle of the projection ...
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Illumination properties of black lights
An elderly friend of mind whose eyesight is fading recently asked me if there was a way to illuminate her new induction stove top so that the "burner rings" would be easier to see, to her it just ...
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Is it possible to adapt the design and principle of operation for a tunable microwave photonic notch filter to a visible light photonic notch filter?
I just read the 2015 excellent paper , "Tunable microwave photonic notch filter based on sliced broadband optical source".
Is it possible to downconvert a microwave photonic notch filter to a visible ...
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Can all electromagnetic spectra be focused like a laser?
Lasers have a wide range of applications, but can be very costly to produce at high power/intensity. Since light is nothing more than a narrow band of the electromagnetic spectrum, it makes me wonder ...
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Focusing light from a laser shot into one point
I'm planning to build a laser shooting target. Something like this:
In the long term I want to build something advanced like a professional grade target, in which the user is able to tell exactly ...
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