Experimenting with Lights and Filters
1.) First we prepared our equipments, filters and notes. Equipments include: a laser pointer, an LED flashlight, polarizing filters, solar panels, color filters.
2.) Next was experimenting with the polarizing filters to manipulate the amount of light that passes through. Polarizing filters may give us more range than neutral density filters, but this can’t be determined until the neutral density filters are tested. See video below.
3.) Using a multimeter we tested how much voltage was being generated by the solar panel under different lighting conditions (with and without color filters).
a. Solar panel under normal room lighting and under white LED light
b. Solar panel under white LED light with different colored filters, starting from the colors with larger wavelengths to shorter wavelengths (red, yellow, green, blue, purple). The yellow and the blue turned out to be generating the most voltage.
4.) Following the same procedure as above, we tested the amount of current that was being generated by the solar cells.
a. Solar panel under normal room lighting + white LED light
b. Solar panel under white LED light with different colored filters, starting from the colors with larger wavelengths to shorter wavelengths (red, yellow, green, blue, purple).
What we discovered: the color filters block out some of the light. The yellow filter blocks out the least amount of light. The red is the largest wavelength so its frequency is the lowest. This information correlates with the amount of energy that it generates.
f.) Using analog read, we were able to find out and translate the solar panel’s energy with ASCII.
analog read screenshot
circuit for connecting solar panel to analog pin
Here is the code that mapped the sensor value from 30 – 400 to 0-1023, so we could get a more accurate reading.
“// Analog Input from LED Light to Silicon Solar Panel
int mapThis;
void setup() {
Serial.begin(9600);
}
void loop() {
int sensorValue = analogRead(A0);
//to have a wider range and higher sensitivity
// map 400 (our potentially highest reading) to 1023
mapThis = map(sensorValue, 30, 400, 0, 1023);
//prints out ASCII
Serial.println(mapThis);
delay(500);
}”
*** Next steps are to connect the readings to a p5js sketch so there is a visual to help illustrate the readings, do the Synchronous Serial Communication lab, and use the flux sensor. To be updated by soon.
*** Full disclosure: for my research and experiments with solar energy and light, I am learning from and collaborating with Dr. Sardashti (Kasra), a material scientist and applied physicist, whose has done research on solar cells.
To do list for this week (10/31/18 – 11/6/18):
a.) figuring out what to communicate (user interviews)
b.) gaining inspiration from a math or science museum
c.) researching + experimenting with different light conditions + filters
d.) doing the synchronous serial communication lab
e.) drawing a new diagram of the interactive table
f.) building a prototype house (also for fabrication)
g.) creating a timeline/ game plan / materials list
h.) meeting with experts, itp professors, and residents in this field
Emily Lin 