Lab-built Photo-luminescence or Electro-luminescence setups are usually made from scratch from basic components.
Although the main components and their configuration is often very similar, there are some techniques that can be used to enhance the signal to noise ratio in order to detect very weak signals.
For example, free-space signal guiding to the detector is better in terms of collected power compared to optical fiber coupling, compromised with alignment ease and losses.
This task becomes harder as we move to the IR range, where extended InGaAs detectors become too noisy. Additional tricks are needed for this purpose.
What are the main techniques or components that can be implemented in a PL/EL setup to boost its performance?
To enhance the performance of luminescence measurement you can use charge-coupled device (CCD) as the detector, to take full advantage of the multichannel capabilities of the CCD with large bandwidth. This article may be helpful:
https://www.osapublishing.org/josab/abstract.cfm?uri=josab-15-4-1410
Thanks for your answer Roman.
The summary you kindly shared is the well known procedure/checklist to go through for a lab setup.
I can add using free-space rather than fiber coupling, using minimal amount of filters or optical components on the signal route, using cage systems to get a better alignment, using infinity corrected objective lenses, using an appropriate steel box to cover the setup for minimal signal interference, or using plastic tubes along the signal path, using a rho/theta/z stage for the sample to maximize signal collection.. etc.
However, the goal behind the question which would be useful for all of us is, assuming we did all of these direct straightforward fine tuning steps of the setup, and we still could not detect a good signal from our devices as the signal is too weak, what else can we do to increase SNR?
Pay attention to establish short distances for the case of optical excitation as well as for luminescence detection (especially for the case of 4pi solid angle light emission). Here you are able to gain a lot of signal.
One of the main components to detect weak optical signals is the detector. It plays a very serious role in the S/N ratio since it can be considered the main noise source. So one must has low noise detector with high sensitivity and detective.
One can use avalanche photo diodes of photo multipliers. In addition one has to avoid the background light sources. If this is not sufficient one has to cool down the detector to reduce its noise.
The other way is one can filter out the noise by using digital signal processing.
A great help can be obtained by chopping the light received by detector.
Chopping the light help much in extracting its signal from the noise and interference.
Best wishes
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