Transcript Portable Low Cost Optical Spectrometer

The GUI interface runs on the Windows
operating system on top of the .NET
framework. It is responsible for displaying the
data from the sensor in a tabulated and
graphical form. Each bar in the spectrograph
is colored based on that particular
wavelength. The program also enables the
user to store data for later retrieval.
Microcontroller:
RS-232 Driver:
Power Regulator:
Sensor:
May 7, 2007
Brett Hamilton
Mateusz Wyganowski
Kodin Taylor
Hardware, GUI, Sensor
Microcontroller, PCB, Hardware
GUI, Web Site
Atmel Atmega8
Dallas Maxim MAX232A
Linear LT3461A
TSL1401R
Recently, easy to use linear-array light detectors have become available at very low cost. By
designing circuitry and software for the interfacing to these sensors a portable and low-cost
spectrometer was made.
Graphical Interface
The software is also responsible for
configuring various operational parameters
of the microcontroller such as the sensor
clocking frequency or serial communication
parameters. The parameters names and
values are read from the microcontroller
dynamically.
A spectrometer is used to measure the properties of light over
a specific wavelength range. it consists of a slit, a light
dispersing element (prism or grating), lenses, and a light
detector. The slit creates a beam of light which is dispersed by
the prism or grating over the detector.
Lenses are typically used to further focus the light rays. The light detector is interfaced to digital
electronics which may be used to filter, analyze, and/or store the information for later retrieval.
This project has multiple facets of design and implementation:
The sensor is controlled by two digital
inputs – a clock and a signal. The sensor
outputs an analog value for each of the
128 photodiodes on the chip at a rate of
about 8 kHz.
Arrangement of optics
Microcontroller Configuration
Lastly, the software features facilities to
automatically calibrate the normalization
values in order to compensate for the
sensor’s uneven response to varying
wavelengths. This requires as input a known
set of data for an element, and the current
reading of the same element.
PCB with Microcontroller
And supporting hardware
User Interface
Lenses, photosensors and prism
Electronics:
Commercial Enclosure
Total
$107.00
$450.00
$557.43