A Conversation for Pulsed Laser Systems
Typo?
Wick Started conversation Mar 10, 2003
In Q-switching its is stated that the burst length is equal to the cavity length MULTIPLIED by the speed of light. Surely this should be cavity length DIVIDED by the speed of light.
Wick
Pedantry
Peet (the Pedantic Punctuation Policeman, Muse of Lateral Programming Ideas, Eggcups-Spurtle-and-Spoonswinner, BBC Cheese Namer & Zaphodista) Posted Mar 10, 2003
"It can be shown that the greater the difference between the pulse length and the pulse spacing, the larger the peak power."
The difference between a pulse length of 1 second and 1 millisecond spacing is identical to that between a 1 millisecond pulse and one second spacing, but the peak powers would be entirely different. That sentence is at best imprecise, and needs rephrasing... 
Pedantry
Euan - † - Getting a new laser to play with - woohoo Posted Mar 11, 2003
Both good points.
I need to read the final version of this thoroughly to check whether there were errors introduced in the Sub process too, but there may have been some I missed originally. THanks for letting me know about these two.
Euan
Pedantry
Smij - Formerly Jimster Posted Mar 11, 2003
If you'd like to suggest how this might be resolved, I can make any changes you feel are necessary. 
Jimster
Pedantry
Euan - † - Getting a new laser to play with - woohoo Posted Mar 11, 2003
Hi Jimster.
OK. The section that Peet mentioned above should be changed to
"It can be shown that the larger the pulse spacing is compared to the pulse length, the greater the peak power"
Wick's point is correct too. The word should be divided.
Also, in the table towards the bottom of the page, on the row beginning "Solid-state Q-switched", the columns fopr repetition rate and duty cycle are back to front. Could you switch these, please?
I think that's it, but there may be more.
Euan
Pedantry
Smij - Formerly Jimster Posted Mar 11, 2003
Made those changes, but I wasn't sure about the columns. Do you mean just the headers (which is what I've done) or that the entire column should swap?
Pedantry
Euan - † - Getting a new laser to play with - woohoo Posted Mar 11, 2003
Neither, actually. Sorry, that was a bit vague. If you can change them back, and then swap the 1000 and kHz-MHz around too. That should do the trick, so that the bits with *Hz are in the same column (marked repetition rate) and the ones which are purely numbers are in the other (marked duty cycle).
Pedantry
aaallan Posted Apr 15, 2005
"It can be shown that the larger the pulse spacing is compared to the pulse length, the greater the peak power"
Er, I'm still not sure this is quite right. A laser pulse of, say 1 Watt lasting 1uS repeated once per second has a peak power of 1 Watt. The same 1uS pulse repeated once per year still has a peak power of 1 Watt.
It's not the peak power that increases, it is the average power that decreases.
Isn't it?
Allan
Key: Complain about this post
Typo?
- 1: Wick (Mar 10, 2003)
- 2: Peet (the Pedantic Punctuation Policeman, Muse of Lateral Programming Ideas, Eggcups-Spurtle-and-Spoonswinner, BBC Cheese Namer & Zaphodista) (Mar 10, 2003)
- 3: Euan - † - Getting a new laser to play with - woohoo (Mar 11, 2003)
- 4: Smij - Formerly Jimster (Mar 11, 2003)
- 5: Euan - † - Getting a new laser to play with - woohoo (Mar 11, 2003)
- 6: Smij - Formerly Jimster (Mar 11, 2003)
- 7: Euan - † - Getting a new laser to play with - woohoo (Mar 11, 2003)
- 8: Smij - Formerly Jimster (Mar 11, 2003)
- 9: Euan - † - Getting a new laser to play with - woohoo (Mar 11, 2003)
- 10: Smij - Formerly Jimster (Mar 11, 2003)
- 11: aaallan (Apr 15, 2005)
More Conversations for Pulsed Laser Systems
Write an Entry
"The Hitchhiker's Guide to the Galaxy is a wholly remarkable book. It has been compiled and recompiled many times and under many different editorships. It contains contributions from countless numbers of travellers and researchers."