Building a realtime phase-space and timeseries plotter for a Simple Pendulum using Arduino Uno & Simulink

Reading time: 4 min 44 sec

Note: This post is intended for educational purpose. This post gives you some insights and details regarding the topic. The contents are structured to enable you to do this DIY project by yourself!

These days, it’s pretty much straight forward to simulate physical systems in a computer. Running those governing equations in any high-level languages such as Python, Visual Basic, Java, etc., make our life easier. Visualization of complex concepts of mainstream subjects is easier than ever before. Thanks to the growing community of coders!

But it is far more interesting when these computer codes interact with real physical systems which we can be touched and smelled! This opens up unlimited opportunities to probe and understand the complexities of a physical system easily. Successful communication between computers and physical systems is usually ensured by some external interfacing device which bridges the data processing between a computer and a physical system. This interface is capable of controlling and interpreting the signals to and from the computer. Though it was hard to implement such devices before, recent advanced technologies combined with novel inventions enable us to do successful interfacing effortlessly. Let’s begin!

Continue reading “Building a realtime phase-space and timeseries plotter for a Simple Pendulum using Arduino Uno & Simulink”

Finite and infinite conjugate objectives

Reading time: 1 min 2 sec

An objective is nothing but a compound lens, like a normal lens, the only difference is they are much more potent in terms of numerical aperture, resolution and magnification. In microscopes, objectives are mainly used with two optical designs: finite or infinite conjugate designs. In a finite optical design, the light from a spot is focused into another spot with the aid of a couple of optical elements, and in an infinite conjugate design, the diverging light from a spot is made parallel.

Taking Fourier plane out of an objective.

Reading time: 2 min 14 sec

We know that a lens is a Fourier transform engine, which does complicated Fourier calculations of a complex object, faster than any computer available today! An object placed at a distance d from the lens will form its Fourier image at the back focal length (f) of the lens. As we know, Fourier image is always formed at the focal plane of the lens, irrespective of the position of the object; it can be very close to the lens (d<< f) or very far away from the lens (d>>f).

How to screen a femtosecond laser pulse stream on an oscilloscope?

Reading time: 1 min 42 sec

It is quite possible to view the pulse stream of a femtosecond output on an oscilloscope screen, especially to measure the repetition rate of the laser. It is to be noted that, we cannot see the pulse shape of the laser beam as the response time (rise and fall time) of the photodiode (PD) is quite higher than the pulse width of the femtosecond laser.

Things to be noted: