Talk:Collimated beam

message: The light reaching me from that part of the sun that I see at the left edge of the sun's disk is not parallel to that from the right edge, since they're half a degree apart.  Is it because 1/2 degree is so small that it's considered collimated, or should the article's statement to that effect be considered an error? Michael Hardy 01:21, 8 Nov 2004 (UTC)
thread_title: Small-angle non-collimation

message: I agree that this should be combined with and redirected to collimating lenses. axharr 21:36, 4 Nov 2006 (EST)
I very strongly disagree that the Collimating Lens stub should be merged into Collimated Light or vice versa. Collimating Lens topic needs to address the action and even the design of collimators, at a minimum using lenses with coherent light (a pretty easy place to start). An example or three with actual numbers would be appreciated, as well. Collimated light needs to be specific about the parallelism of rays in a collimated beam, interference patterns between coherent spherical wave fronts and (mutually) coherent plane (collimated) wavefronts and/or spherical wavefronts, etc.  --Light should describe the beam, --Lens should describe the apparati. Onlyocelot 11:03, 21 April 2007 (UTC)
replies: text: Great. Now we've ended up with a section in this article that says it covers lenses, but the text of that section only discusses mirrors and... flight simulators (which is just weird). Looks like a hack job was done in this respect.  Any thoughts on what ought to be done now? KDS4444Talk 00:29, 3 June 2015 (UTC)
thread_title: Combine with Collimating Lenses?

message: Collimators for Thermal Neutron Radiography an Overview  by J.C. Domanus and J.F.W. Markgraf (Jan 1, 2001)
Areal parabolic collimators for the Keck II telescope (Lick Observatory technical reports)  by Brian M Sutin (1995)  
:-vs-
Absorption and Scattering of Light by Small Particles (Wiley Science Paperback Series)  by Craig F. Bohren and Donald R. Huffman (1998)
Interferometry in Speckle Light: Theory and Applications  by P. Jacquot and J.-M. Fournier (Oct 27, 2000)
Stephenkoski 07:13, 2 May 2007 (UTC)
thread_title: A bibliography a propos of?

message: I think that the sentence "Most amateur reflector telescopes need to be re-collimated every few years to maintain optimum performance" is a bit misleading. Many amateur reflector telescopes are Newtonians/Dobs, and their users should probably better collimate them before every observing session, especially if the telescope was moved.
--M. Tewes (talk) 19:45, 6 January 2012 (UTC)
replies: text: You're replying to a post that is five years old...--Srleffler (talk) 03:45, 21 September 2017 (UTC)
thread_title:  Frequency of collimating a telescope 

message: These concepts seem similar at least on the surface, although nothing relating to collimation is mentioned in the article on coherence or vice-versa. I'd assume coherent light would by implication be collimated. --Rimmer7 (talk) 22:26, 27 September 2016 (UTC)
replies: text: Not all coherent light is collimated. Spatial coherence is a prerequisite for good collimation, though.--Srleffler (talk) 04:28, 28 September 2016 (UTC)
thread_title:  Collimation relation to coherence?