Differences

This shows you the differences between the selected revision and the current version of the page.

group2:demonstration_and_results 2008/12/09 15:56 group2:demonstration_and_results 2008/12/09 16:32 current
Line 9: Line 9:
-The spectrometer performed according to expectations and the resulting plots were reasonable. The first trial produced a graph with a short wavelength, with a mean peak of 481 nm. The second trial produced a longer wavelength with a mean peak of 650 nm. The third was longer than the second with a mean peak of 615 nm. The fourth was longer than the third with a mean peak of 561 nm. From these results it may be deduced that the first trial was for the blue LED, the second was for the red LED, the third was the yellow LED, and the fourth was the green LED. +The spectrometer performed according to expectations and the resulting plots were reasonable. The first trial produced a graph with a short wavelength, with a mean peak of 481 nm. The second trial produced a longer wavelength with a mean peak of 650 nm. The third was shorter than the second with a mean peak of 615 nm. The fourth was shorter than the third with a mean peak of 561 nm. From these results it may be deduced that the first trial was for the blue LED, the second was for the red LED, the third was the yellow LED, and the fourth was the green LED.
To observe the relative position of each LED in the spectrum, the following graph presented summarizing the results: To observe the relative position of each LED in the spectrum, the following graph presented summarizing the results:
-{{:group2:trial_final.jpg|}}+{{:group2:final_test_result.jpg|}}
After the demonstration a white light source was analyzed using the spectrometer. The result was the spectrum covered the entire range of the four single-coloured LEDs. There are two peaks on the spectrum, corresponding to separate optical mixtures in the source used to approximate white light.  After the demonstration a white light source was analyzed using the spectrometer. The result was the spectrum covered the entire range of the four single-coloured LEDs. There are two peaks on the spectrum, corresponding to separate optical mixtures in the source used to approximate white light. 
Line 20: Line 20:
 +The results of our spectrometer were compared to those of the LED specification sheets. The blue corresponded to a mean peak of 464 nm (-17 nm deviation), the red corresponded to 645 nm (-5 nm deviation), the yellow to 591 nm (-24 nm), and the green to 515 nm (-46 nm). This deviation was due the diffracted light arriving at the photodiode from different angles. This results in a wavelength distribution that is nonlinear across the spectrum.
 +
 +The purpose of this project was to differentiate the colours of four LEDs. Our final design and product have demonstrated that it can indeed differentiate between: red, blue, yellow, and green. Therefore the spectrometer had successfully performed the task the group had intended.

Personal Tools