| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| khufkens | "I'm making a simple spectrometer to extract the spectral response curves of an imaging sensor. To this end I made some calculations to help me desi..." | Read more » | over 9 years ago | |||
| MrBumper | "I don't know if this will clarify anything, but I'm finding using a laser beam from a red laser pointer quite useful in examining what goes on with..." | Read more » | over 9 years ago | |||
| cfastie | "I don't know whether you could see a clear projected image of the spectrum. I think you could, but it would rather small and dim. I also don't know..." | Read more » | almost 10 years ago | |||
| wizard | "Wow... excellent information... thanks. I am a newbie, and my questions will be indicative of that.... I see now that I may assemble two spectrome..." | Read more » | almost 10 years ago | |||
| Tom_H | "I was able to get a copy of the article. From a brief scan it looks very pertinent to what we are doing/discussing, but I have not really read it y..." | Read more » | over 11 years ago | |||
| cfastie | "Well done,Tom. This article which was mentioned at the Google group, discusses the issue of focusing on the spectral image. It even has an equatio..." | Read more » | over 11 years ago | |||
| Tom_H | "maybe I have it now " | Read more » | over 11 years ago | |||
| Tom_H | "Your text to link...O.K. I am going to try to insert drawings from Picasa: it seems I haven't learned to do imbedding, but here is the link htt..." | Read more » | over 11 years ago | |||
| cfastie | "The Google group is completely separate from this web site, so the two places have somewhat independent conversations. I guess the Google group is ..." | Read more » | over 11 years ago | |||
| Tom_H | "Chris, I will work on doing an upload somehow. I have plots-spectrometry in my google groups, but I can't find these research notes there. " | Read more » | over 11 years ago | |||
| cfastie | "Tom, images would be very helpful (so my mind doesn't explode). If you upload images to a site like Flickr or Picasa you can grab the HTML embeddin..." | Read more » | over 11 years ago | |||
| Tom_H | "Hi straylight, You make some good points, and I think you need to think more about a couple of things. 1) Even with a slit small enough to produc..." | Read more » | over 11 years ago | |||
| straylight | "Chris, you said: "At certain grating angles, it is not possible to see a sharp image of the spectrum when the grating is too close to the slit. Bu..." | Read more » | over 11 years ago | |||
| Tom_H | "I think the reason that Chris has trouble getting good resolution at certain angles has to do with the eye's focusing mechanism, and the focus may ..." | Read more » | over 11 years ago | |||
| cfastie | "Stu, Thanks for the lesson! It’s really good to get a feeling for these concepts. I wish you had been my high school teacher. TomH sent me a spre..." | Read more » | over 11 years ago | |||
| straylight | "well done cfastie, thanks for taking the time to conduct some measurements. I've been pondering over the pattern and the angles for some time now. ..." | Read more » | over 11 years ago | |||
| straylight | "oh yeah, Love the lego optical bench and the discussion in the other research note. stu " | Read more » | over 11 years ago | |||
| cfastie | "I am glad you raised the question of how the distance to the slit could affect how much the light was bent when it hit the diffraction grating. Thi..." | Read more » | over 11 years ago | |||
| Tom_H | "What you are observing here may be related to what is referred to as the "blaze" angle of the grating. For actual diffraction gratings, the indivi..." | Read more » | over 11 years ago | |||
| Tom_H | "The basic grating equation works for transmission as well as reflection. The sign conventions can throw you though. One purpose of the collimatin..." | Read more » | over 11 years ago | |||
| liz | "This is amazing! I also like Dan Beavers graphic :) " | Read more » | over 11 years ago | |||
| cfastie | "Yes, now I have it. When the entrance slit is rotated the rectangular spectral image turns into a parallelogram. It seems to get compressed vertic..." | Read more » | over 11 years ago | |||
| danbeavers | " I hope this illustrates what I mean. " | Read more » | over 11 years ago | |||
| cfastie | "Tom, The Jobin Yvon tutorial describes reflection gratings, and I don't know enough to apply those rules to our transmission grating setups. The ma..." | Read more » | over 11 years ago |