Workshop Banner
* Home Button Venue Button Program Button Register Button Lodging Button Abstracts Button Contacts Button * *

13th International Laser Ranging Workshop
"Toward Millimeter Accuracy"

Submitted Abstracts
Laser Technology Development (K. Hamal and Howard Donovan, for Y. Gao)

Title Primary Author
Kilohertz Laser Ranging at Graz Georg Kirchner

Austrian Academy of Sciences
Observatory Lustbuehel
Lustbuehelstrasse 46
A-8042 Graz
AUSTRIA
Voice: +43-316-873-4651
Fax: +43-316-873-4641
Email: kirchner@flubpc04.tu-graz.ac.at

Franz Koidl
Austrian Academy of Sciences
Observatory Lustbuehel
Lustbuehelstrasse 46
A-8042 Graz
AUSTRIA

At present, SLR Graz is ranging to all satellites with a standard Nd:YAG Laser, with 10 Hz repetition rate, using SemiTrain pulses with a total energy of about 30 mJ per shot and a pulse length of 35 ps; we intend to replace this 20 years old system with a diode pumped, solid state laser, operating with 1 kHz repetition rate nominally (10 Hz to 2 kHz specified), with single pulse energy of 0.5 mJ per shot at 532 nm, and a pulse length of 10 ps.

While the present laser system will remain operational for special experiments like MultiColor Ranging etc., the expected advantages of the new laser system are up to kHz return rates for all low satellites, significantly improved return rates from LAGEOS, and same return rates from high orbiting satellites as now; this should map into much better defined Normal Points for all satellites up to and including LAGEOS.

Most requirements to implement such a laser system into the SLR station have been built or installed already during the last years: The Graz Event Timer (E.T.) - operational since autumn 2000 - already allows repetition rates of up to 2.5 kHz; a new Range Gate Generator has been designed and built in Graz to allow kHz repetition rates, while defining the Range Gate with 500 ps resolution.

The necessary budget for this project has been applied for, but we are still waiting for a final decision.

Oral paper; received August 9, 2002

   
Mechanical measurement of laser pulse duration Jean-Louis Oneto

OCA/CERGA
Avenue Copernic
06130 Grasse
FRANCE
Voice: +33.4.93.40.53.80
Fax: +33.4.93.40.53.33
Email: oneto@obs-azur.fr

Jean Gaignebet
OCA/CERGA
Avenue Copernic
06130 Grasse
FRANCE

An original interferometric device has been developped, which allows to measure the duration of laser pulses in the picosecond domain, with a precision of few percent. This could be a cheap and convenient alternative to the streak-camera methods available today.

Oral paper; received August 22, 2002

   
Lasers for Multiwavelength Satellite Laser Ranging Karel Hamal

Czech Technical University
Brehova 7
115 19 Prague 1
CZECH REPUBLIC
Voice: +420 2 21912246
Fax: +420 2 21912252
Email: prochazk@mbox.cesnet.cz

I. Prochazka, J. Blazej
Czech Technical University
Brehova 7
115 19 Prague 1
CZECH REPUBLIC

Yang Fumin, Hu Jingfu
Shanghai Observatory
CHINA
Jean Gaignebet
Grasse
FRANCE

To find the right laser for multiple wavelength millimeter SLR one can consider he NdYAG / SHG / THG, NdYAG / SHG / Raman in Hydrogene/1S/1aS and the Titanium Sapphire fundamental / SHG at different repetition rates. Our optimization of the four wavelengths Raman laser at 1.064, 0.53, 0.68 and 0.45 um gives 60, 20, 7, 2 mJ at 20Hz for 35 psec pulses. The laser setup, conversion efficiencies and the far field beam structure will be displayed. The laser is dedicated for the new Shanghai SLR station.

Oral paper; received August 22, 2002

 
High-Power, Short-Pulse Microlaser - Power Amplifier System Yelena Isyanova

Q-Peak, Inc.
135 South Road
Bedford, MA 01730
USA
Email: isyanova@qpeak.com.

Kevin F. Wall, John H. Flint and Peter F. MoultonQ-Peak, Inc.
135 South Road
Bedford, MA 01730
USA

John Degnan
NASA Goddard Space Flight Center
Code 920.3
Greenbelt, MD 20771
USA

Presented by Peter Moulton

Passively Q-switched Nd:YAG/Cr:YAG microlasers are simple, compact and reliable sources of high repetition rate (100 Hz to 20kHz), near-infrared, sub-nanosecond pulses. To date, low-energy (1 to 10 mJ/pulse) and mid-energy (10 to 50 mJ/pulse) microlasers are commercially available with pulse durations of 600 to 1000 ps. For some applications, for instance, high precision ranging and imaging, higher-energy pulses, as much as 500 mJ/pulse, are required with pulse durations approaching 200 ps. In this work, we report on a prototype of a Laser Transmitter (LT) for the NASA SLR2000 system, generating 335 mJ at 1064 nm with efficient (60%) harmonic conversion to the visible and pulse durations below 400 ps. The LT is based on the use of a MOPA design with a microlaser oscillator and multipass Nd:YVO4 amplifier. In recent work we have achieved 15-mJ pulses at 1.06 mm from our microlaser, with pulse durations in the green as short as 270 ps.

Oral paper; received September 19, 2002

top

Content Owner and Webmaster: Carey Noll
Responsible NASA Official: Ed Masuoka
Last Updated: September 25, 2002

 


HOME | VENUE | PROGRAM | REGISTER | LODGING | ABSTRACTS | CONTACTS

Workshop Footer