Abstract
This project is a drone calibration device to find the orientation of the polarization of light in the optical spectrum. It is a proof of concept project; therefore,
if it works in the optical spectrum it will then be done for millimeter wavelength
light. Ultimately, the goal of this project will be to use the polarization of the
ambient background of millimeter wavelength light to determine if gravitational
waves from the early universe can be detected.
The project itself is devised of two main instruments: the polarimeter and
the drone calibration source. The polarimeter, in order of light hitting the
instrument, consists of a rotating half wavelength plate, a linear polarizer, a
lens, and a camera. Additionally, there is an encoded motor that rotates the
half wavelength plate to vary the intensity of a specific frequency of light. As
the half-wavelength plate is rotated, it rotates the polarization of the light;
therefore, allowing more or less light in through the linear polarizer. The half-
wavelength plate is set for a specific frequency so it doesn’t block all light just
light at a specific frequency, here the frequency lines up with the color green.
Thus, the goal of the polarimeter is to show the correlation of the calibration
source’s intensity versus motor angle position, which in theory will create a sine
wave. Then one can use the phase of this sine wave to find the orientation of
the polarization of the light. The second half of the project is the calibration
device, an LED of the same frequency as the half wavelength plate mounted
on a drone along with another camera and a beamsplitter. The drone acts as
a calibration source for the polarimeter that is at an “infinite” distance away
from the polarimeter. Thus, the polarization of the source can then be used
as a standard measuring tool against the ambient background light. Through
using the orientation of the drone and the polarization of the background light,
the effects of gravitational waves can possibly be detected. The future goal for
this project is upgrading both the drone to a CubeSat that will orbit the Earth
and the polarimeter to a finer tuned polarimeter, possibly one at the Simon’s Observatory Telescope.
