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Re: starship-design: Laser or maser?



At 11:57 AM 10/29/96, Timothy van der Linden wrote:
>Kelly replied:
>
>>>300 and 385 kilometer diameters don't seem like a headache...
>>
>>A 300-400 kilometer laser array?  Again it would be a bit hard to fit on
>>our moon.  Harder to sycronize since the frequencies are shorter.  Also the
>>sail has now gone from a wire mesh to a reflective sheet.
>
>Hard to fit on the moon? I don't understand, its diameter is 3476 kilometers.
>The frequency is indeed increased by a factor 3, however having a solid
>floor helps a lot.

If you have to find a position for the array that has constant direct line
of sight at all times.  Your limited to a small polar region.  The farther
the target star is from true north or south the narrower the polar region.
Also the platforms must be in direct line of sight so they can adjust for
one anothers movement (yes platforms mounted on the Moon will more around a
bit).



>I wonder are semiconductor lasers more efficient and cheaper than ordinary
>lasers. What will be the costs compared to masers which cannot be made in
>semiconductors?

Can't remember.  I thought free electron lasers had the highest efficency?


>Also on the receiving side, what are the pros and cons?
>On the receiver-end we not only need a mirror, but also an absorber. Are
>photocells better than skottky diodes?

Why an absorber?


>Has anyone an idea where to get this kind of information?
>
>What are the disadvantages of a reflective sheet compared to a wire mesh? Is
>it only the weight?
>
>Timothy

Increased drag and more limits in materials I think?

Kelly


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Kelly Starks                    Phone: (219) 429-7066    Fax: (219) 429-6859
Sr. Systems Engineer                                     Mail Stop: 10-39
Hughes defense Communications
1010 Production Road, Fort Wayne, IN 46808-4106
Email:  kgstar@most.fw.hac.com
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