Standard Lidar Scanners

DFM Engineering is a leading supplier of custom system components to the companies that are defining the parameters and creating new uses for LIDAR technology.

With experience in custom-designing and building high quality, research-grade telescopes since 1978, we deliver the proven components you need for a competitive edge.

Our elevation-over-azimuth scanner design gives you full sky coverage with PC computer control. We include full documentation and software source code written in high level language for easier customization and maintenance.

No matter which direction LIDAR development takes you, look to DFM Engineering for scanners and accessories, including Optics-In-A-Box™ beam expanders/compressors.

Applications include:
• pollution monitoring and enforcement
• fugitive dust detection
• clear air turbulence
• meteorological research

4 in. to 18 in. Standard Design Features:

  • two flat mirrors in an elevation-over-azimuth mounting
  • Incoming light is reflected 90 degrees from the elevation mirror to the azimuth mirror which then bends the light downward 90 degrees.
  • design gives you 1/100 degree pointing resolution and enhanced position displays
  • DFM Scanners and optics offer custom capabilities used for remote sensing.


Lidar Components
DFM Engineering has provided many Electro-Optical-Mechanical Systems™ (EOMS™) in scanners used for Light Detection And Ranging (LIDAR) remote sensing applications.

Typically these scanners are an Alt-Az Coude' form of a beam director using two flat mirrors.

The major difference between a LIDAR scanner and a beam director is the scanner has a lower angular resolution and a higher speed. The optics may be of lower optical figure because of the longer wavelengths often used.

The scanners may also incorporate additional EOMS™ components such as collimating optics, zoom lenses, focus motion, fiber feed, etc.

DFM Engineering has designed and manufactured over 30 EOMS™ incorporating these features that were used to measure the atmospheric turbulence. Three were near a helicopter landing ship where stabilization of the scanner to correct for a ship's roll, pitch, and yaw has also been provided.

One custom LIDAR scanner was a airborne project for NASA. You can learn more in our news section:
NASA Goddard selects DFM Engineering, Inc. to build Airborne Lidar Telescope
NASA’s Ramen Airborne Spectroscopic Lidar instrument progress report
NASA RASL Telescope ships

Lidar Scanner Specifications

MECHANICAL:
• Rugged, anodized aluminum and stainless steel construction
• Maintenance-free sealed bearings
• Sealed elevation storage window (not available on 4 in. scanner)
• DC servo motors drive the axes
• Accurate positioning by optical encoders
• Enclosed elevation axis drive

ELECTRONIC:
• IBM-compatible PC computer with custom DFM I/O card provides control interface to the scanner scanner
• Power supplies, control logic hardware and servo motor controllers are contained within the motor driver chassis
• Pulse rate generators produce motion commands to motors
• Up-down counters monitor axes position by counting pulses from incremental optical encoders
• A full electronic drawing package is included
• The PC monitor provides scanner information display - including large graphical displayed azimuth and elevation angles in degrees (DD.DD) for easy viewing at a distance
• 3-speed hand paddle for manual control

SOFTWARE:
Disk-based control system software written in high level language
Easy maintenance and modifications
Full software listings and documentation
Nine commands provide complete control via serial or 8-bit parallel interface
• 0 Immediate stop both motors
• 1 Initialize azimuth position display to specified value
• 2 Initialize elevation position display to specified value
• 3 Read current azimuth and elevation positions
• 4 Load raster scan data
• 5 Start raster scan
• 6 Load coordinate scan data
• 7 Start coordinate scan
• 8 Move to specified position
Dimensions
Performance Specifications

  LIDAR Optical Tube Assembly
Optics-In-A-Box™ was designed by DFM Engineering to provide Beam Expanders/Compressors for LIDAR System Integration.

In addition to LIDAR scanners, DFM can provide bench-mounted optical assemblies for use with your LIDAR system.

Utilizing proven components, we will provide a custom designed optical system with optical coatings to meet your requirements. 

Optics are assembled in a compact, dust tight enclosure that saves space and protects the mirror coatings. Invar mirror spacers are used for passive focus stability. 

The custom mechanical design provides for mounting to your optical bench. However, any mounting orientation is available, with horizontal for LIDAR vans or down-looking for aircraft being the most common.

 

Lidar Scanner Performance Specifications

4 Inch

8 Inch

12 Inch

18 Inch

Clear Aperture

120 mm

8 inches

12 inches

18 inches

Resolution

10 micro radians

1/100 degree

1/100 degree

1/100 degree

Speed

60 deg/sec

30 deg/sec

30 deg/sec

30 deg/sec

Acceleration

60 deg/sec^2

30 deg/sec^2

30 deg/sec^2

30 deg/sec^2

Weight

170 lbs

260 lbs

300 lbs

650 lbs

Optics Figure

1/10 Peak Valley @ 1 micron

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Surface

60/40 scratch/dig

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**Optics and coatings per customer specifications