“BEAMS”49 pages
- p. 3 …Free-Electron Laser Electron Beam Phase-Space Evolution ....................... 59
Figure 31. Recirculating-Beam FEL System ........................................................... 60…
- p. 4 …HEL Beam Pointer/Tracker ................................................................... 65
Figure 35. Basic Shared Aperture Beam Control System ......................................... 66
Figure 36…
- p. 7 …This can only be achieved via laser propulsion in
which the laser beam energy that is…
- p. 15 …By launching
spacecraft on a beam of electromagnetic radiation, researchers will have developed the
first new…
- p. 16 …The laser beam's pulse
interacts with the mirror, spreading out and focusing into an annular…
- p. 17 …1) power supply; 2) high-power (megawatt-class)
laser beam generator/transmitter using novel beam optics…
- p. 20 …is to the right and the laser beam strikes the stretched-out parabolic
mirror/propulsion section…
- p. 21 …It
requires a beam power of 0.1 to 1 MW per kg of vehicle mass…
- p. 22 …The ground-based
megawatt-class laser beam generator is state-of-the-art technology. The cost…
- p. 25 …Figure 8 illustrates the adverse beam
propagation geometry associated with ETO laser propulsion by means of…
- p. 26 …Attenuation Effects on Captured Laser Beam Power 261.
0.4
0.J
0.2
0.1…
- p. 27 …Unfortunately the demonstrated laser beam power levels for the attractive 1.62 μm
wavelength, which suffered…
- p. 28 …Beam combining
of several 1 MW (or higher) FELs can achieve a total combined beam output…
- p. 31 …Appropriate rotation of a high-energy laser beam,
emanating from a ground/sea-based laser, guides…
- p. 32 …Appropriate rotation and translation of a high-energy laser
beam, emanating from a moving aircraft, guides…
- p. 33 …But
multiple target interception within allowable time is limited by relatively long beam-
riding time needed…
- p. 37 …In this case, it is envisioned that the high-
pulsed power within high-energy laser beams…
- p. 39 …In this case, airborne laser beams at 12 km altitude will not suffer the
significant propagation…
- p. 41 …sidelobes, creates multiple beams, and steers the ensemble of the
individual beams anywhere on Earth. The…
- p. 42 …Each picosat is gravity-
gradient stable, has a dipole array facing Earth, and a broader beam…
- p. 43 …Commands for beam sweep delays are superimposed on the time delays of each
nanosat. Each nanosat…
- p. 44 …piezoelectric membrane kept flat by an electron beam in response to an optical figure
sensor. MEMS…
- p. 46 …technical issues include large wavelength and
atmospheric absorption of the laser beam.
• Carbon Monoxide (CO) Laser…
- p. 47 …125 Hz@ 20μs.
• Laser power, P = 2.5 MW/beam x 4 beams = 10 MW.
• Laser…
- p. 50 …Each power oscillator optics module transmitting a 2.5 MW beam of
10.6 μm wavelength…
- p. 52 …Adding an eight amplifier chain that the system was designed for will
increase the beam power…
- p. 53 …However,
BSSSL beam power can be scaled up further by improving presently known gain media
and…
- p. 54 …scalable
to 1 MW beam power within 2 years.
Typical solid-state lasers have the following…
- p. 55 …A new technology that enables the scaling-up of BSSSL beam power is a recently
developed…
- p. 56 …at the same time increasing the average
beam power.
Figure 21. Phase Change Materials Allow Storage…
- p. 57 …This exponential growth in beam output power is the result of many factors,
including the parallel…
- p. 58 …Microlens -O _
,:1
Incoherent Beam Combining 'Ind1vidually Incoherent Gaussian Beams i=L
Controlled
/_/Steering • ... o~bined…
- p. 59 …Neodymium
Thulium (Tm 3+), Holmium
- Range of beam wavelengths(),) produced: 0.48 μm to 2.9…
- p. 61 …Multlmode Fiber Lasers
50kW Multimode
Output beam quality BPP-1 o
M"2-33
DC EDE…
- p. 62 …The resulting laser beam photon energy depends on the
electron energy, the undulator period, and (weakly…
- p. 63 UNCLASSIFIED/ /F8~ 8FFl&I.«1k WliEii a,.klf
electron beam
( \ I,:--- ■■>ti■--
undulator
)
resonator mirror
0…
- p. 64 …The superconducting accelerator gives good
efficiency and gradient while recirculation of the electron beam recovers beam…
- p. 65 UNCLASSIFIED/ /F&~ 8FFHiil.«1k 1!181! &••kY
- K"' 1.5.t
• Electron Beam:
- Photocathode injector creates…
- p. 66 …HIGH ENERGY LASER BEAM CONTROL
··costs could be reduced to as low as $20 per kg…
- p. 67 …The typical HEL beam control system includes:++ 1) a gimbaled
beam director, 2) tracking and pointing…
- p. 68 UNCLASSIFIED//F&II. &FFiii,111!! l!llili &HI!¥
A novel new HEL beam control architecture being…
- p. 69 …HEL Beam Pointer/Tracker (courtesy of the Directed Energy Professional
Society).
In summary, this new architecture…
- p. 70 …The BILL is a solid-state, kilowatt-class laser
that measures atmospheric conditions, allowing the beam…
- p. 71 …All of these HEL beam control innovations can be quickly adapted to laser propulsion
applications with…
- p. 72 …The entire Lightcraft launch
system is comprised of a ground, sea, or airborne laser beam generator…
- p. 73 …New beam
control devices and high-power optical train combinations have a resulting beam line
that…
- p. 75 …N. (1983), "Advanced Beamed-Energy and Field Propulsion Concepts,"
BDM/W-83-225-TR, BDM Corp…
- p. 76 …N. (2001), "World Record Flights of Beam-Riding Rocket Lightcraft:
Demonstration of 'Disruptive' Propulsion Technology," AIAA…
- p. 77 …of the 6 th Int'! Symposium on Beamed Energy
Propulsion, edited by C. R. Phipps, AIP…
UNCLASSIFIED/ ,,roAt OFFIQI.Ctk WliEii ·••LY
propulsion requires a modest 0.1 to 10 MW of total beam power. The ground-based
megawatt-class laser beam generator is state-of-the-art technology. The cost of
generating electrical power for the ground-based laser beam generator is ~ $0.10/kWh,
which translates to< $2/kg of payload. An SDIO study [10, 11] showed that all launch
to orbit conditions for a Lightcraft could be satisfied by a single, high-power ground-
based laser - with or without the aid of a low altitude laser relay mirror or space-based
laser beam generator system. The majority of the system mass required to launch a
payload to orbit is left on the ground in the form of the beam generators and their
electrical power sources. The dry spacecraft mass can be further reduced by two
orders of magnitude, and thus the operating costs reduced by a factor of 10 (to <
$2/kg of payload), if Buckytubes are used to construct the vehicle and its subsystems.
LIGHTCRAFT NANOSATELLITE CONFIGURATION
As shown in Figure 7, the Lightcraft nanosat configuration consists of: 1) a conically
shaped "forebody" for lift and aerodynamic compression of ingested airflow (prior to its
detonation by laser heating during atmospheric flight); 2) an annular "cowl" or "shroud"
within which air detonation or propellant ablation (by intense laser heating) occurs; and
3) a parabola-shaped "afterbody" whose mirrored surface focuses beamed laser energy
into regions of sufficient smallness for intense air or propellant heating to occur. And as
shown in Figure 8, the vehicle is powered by laser airbreathing propulsion (by
detonation of air) until hypersonic speed within the sensible atmosphere is reached;
and then the vehicle is powered by laser rocket propulsion (by heating of propellant)
during flight above the sensible atmosphere, until cut-off velocity for orbital flight is
reached.
Shroud (Cowl):
within which Laser
Heating of Airflow
and Propellant
Occurs
I
IForebody: for Lift
and Compression
of Airflow during
Atmospheric Flight
Figure 7. Lightcraft Concept [261.
18
---
• Laser Airbreathing Flight
from Zero Velocity to
Hypersonic Speed
--- --- ---
Afterbody: with
Mirrored Surface
for Focusing Laser
Energy into the
Shroud (Cowl) Laser
Beam
·----------- j\ --------- -
\Axi-Symmetric Body
• Laser Rocket Flight from
Hypersonic to Orbital
Speed
UNCLASSIFIED/ /f81il 8ffl@Itltt ""I! one I