Optics
When White Becomes Pale Yellow – The Fundamental Limit Of Colour Measurements
Colour measurement devices often claim to rely on the quality of their calibrations. However, no matter how good these calibrations are, the quality of the measurement is ultimately constrained by the quality of the hardware. It is not possible to just “calibrate away” suboptimal hardware. There is only so much a calibration can do. Using a simple white point calibration, one can easily see what these limits look like, where they come from, and what a calibration is actually doing.
Optics
Designing a Köhler Illumination
A Köhler illumination is a way to create uniform illumination out of a non-uniform source. Most notably, Köhler illumination makes very little use of diffusers, thereby preserving almost all of the source’s optical power. This article shows how to design such an illumination scheme and gives tips and tricks on how to optimise the design.
Programming
The Elegance of Binarised Neural Networks
Binarising neural networks is a method to shorten the time they require to make a prediction. The method is elegant in that it does not add complexity to neural networks but instead takes it away. It turns out that binarisation also makes the inner workings of a neural network more intuitive.
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Optics
DIY Homogeneous Illumination Using an Integrating Sphere
Optical metrologists need homogeneous light sources. Without them, it is difficult to measure the quality of optical systems accurately. Though commercial solutions are an option, they are often expensive. Their high prices are usually not a problem if one needs only a few of them. However, if they are parts of mass-produced products, then their high prices are a problem. In such cases, it is preferable to build one’s own customised light sources. This post shows how to design such a customised light source and uses an easy-to-follow example to demonstrate all steps in a complete optical design. Only standard components and simple manufacturing techniques are used.
