Apparatus for controlling the scan width of a scanning laser beam

Patent · 22 October 1996

OSTI ID:392656

Johnson, G W

Swept-wavelength lasers are often used in absorption spectroscopy applications. In experiments where high accuracy is required, it is desirable to continuously monitor and control the range of wavelengths scanned (the scan width). A system has been demonstrated whereby the scan width of a swept ring-dye laser, or semiconductor diode laser, can be measured and controlled in real-time with a resolution better than 0.1%. Scan linearity, or conformity to a nonlinear scan waveform, can be measured and controlled. The system of the invention consists of a Fabry-Perot interferometer, three CAMAC interface modules, and a microcomputer running a simple analysis and proportional-integral control algorithm. With additional modules, multiple lasers can be simultaneously controlled. The invention also includes an embodiment implemented on an ordinary PC with a multifunction plug-in board. 8 figs.

• Research Organization: University of California
• DOE Contract Number: W-7405-ENG-48
• Assignee: Dept. of Energy, Washington, DC (United States)
• Patent Number(s): US 5,568,255/A/
• Application Number: PAN: 8-321,695
• OSTI ID: 392656
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
ABSORPTION SPECTROSCOPY
CAMAC SYSTEM
COMPUTERIZED CONTROL SYSTEMS
DESIGN
DYE LASERS
LASER RADIATION
REAL TIME SYSTEMS
RING LASERS
SEMICONDUCTOR LASERS