Weekly Reports

Week 8: Oct 20 - Oct 24

The optical proof of principle was completed. It was determined that the use of a slit was far more effective than that of a large pinhole. It would be interesting to investigate a small pinhole, but the slit appears to be the best choice. To make the slit, a wooden frame will be constructed with aluminum foil stretched over it. An exacto knife will be used to precisely cut the slit. The slit will be constructed this weekend. Another piece of equipment which is required is a stage for the prism. It will be held in place with tape and rubber bands between two pieces of wood. Light pressure will be applied to keep the prism in place. This will also be constructed during the weekend. Lastly, several other holders will be created out of wood for lenses and other equipment, as well as a stage for the LED's to be tested. On the electrical side, the photodiode was successfully tested, by moving it into the refracted beam, and reading a voltage via an oscilliscope.

Week 7: Oct 13 - Oct 17

We are still waiting for our diode. In addition, we requested a free sample diode from taos. We have purchased a large bolt and several other supplies for the mechanical part of the project. We also began programming the micro controller: we were able to compile some basic code to get the micro controller to output a square wave.

Week 6: Oct 6 - Oct 10

We did not have much time to do work this week. However, we were able to examine the items which were ordered, and chose the lenses which we need. We were able to calculate the focal length of a couple lenses, and investigate how well the LED is colimated with them.

Week 5: Sept 29 - Oct 3

We have found a prism available from the previous year thanks to Ana. We have also finalized the parts to be order. We decided to order just a single Si photo-diode in order to experiment with how well it detects. If it works well we will work on building a good mechanical system. We also chose all the appropriate electronic parts.

Week 4: Sept 22-26

We had several meetings about the design of the spectrometer. The decision was made to go with the prism design, since the grating has an uneven efficiency curve over different wavelengths. To overcome the very narrow spectrum from the prism, we are going to diverge it with a diverging lens. We have also decided to use a single detector, because it would be too expensive to buy or build and array of photo diodes. We will be moving this diode linearly, so a stepper motor will be needed. We have almost finalized the parts we are ordering, and will have it submitted by Sunday.

Week 3: Sept 15-19

On Monday the group had met to brainstorm possible designs. After a discussion we decided that all member were interested in pursuing the Spectrometer and the Free Space Optical Communications System. On Tuesday the group met again and decided to pursue the Spectrometer as the first choice since we were more knowledgeable in the subject. We brainstormed possible designs for our spectrometer and decided to have a draft copy of a proposal prepared for Wednesday. Each group member was assigned to complete a particular section of the draft report. On Wednesday the group held an online meeting and we each shared our concerns, possible problems, and alternate designs. On Thursday the group met to work on the presentation. We had also addressed a problem we were having with the rotating diffraction grating of our design. Finally on Friday we met briefly to practice our presentation and we had presented our topic in front of the class shortly after.

Week 2: Sept 9-12

- We have met on Friday during the lab and discussed some ideas for the projects - We have decided that we want to chose between the spectrometer and the free space optical communication projects. Our plan for this week was too do some independent research and share our ideas via email Sunday evening. We plan to use the wiki page discussion board for future discussions, but it is unfortunately not available to us right now. We have decided to meet on Monday between our classes, and begin writing the proposals.