al section 
  
Field 
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Z-axis 
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'asures the 
Al-Hanbali, Nedal 
angular position 0 of a given point of interest in the horizontal plane, while the Y-axis scanner (i.e., galvanometer) 
measures the angular position ¢ of the same point in the vertical plane, or vise versa. As shown in the Figure, the 
distance to any point of interest is computed by triangulation. Two mirrors on either side of the Z-axis scanner act as a 
"baseline" and, as the scanning mirror (on the vertical axis between the two fixed mirrors) rotates, the position of the 
returning laser light on the CCD position detector shifts according to the distance from the point of interest. 
The image can also be a single point image (field of view is 0° X 0°). The acquisition speed can be as high as 18 kHz. 
For example, a scene of 512X512 pixels can be captured, using the raster mode, in about 14 seconds. If only a small 
part of the scene is needed to be captured (e.g. vibration monitoring), using the Lissajous mode and 128 elements, the 
scan rate of the scene can be as high as 137 Hz., see Blais et. al.(1991) and Blais et. al.(1993). 
3 DEVELOPED SOFTWARE 
3.1 The Laser Scanner Interface Software: 
A friendly user interface was especially 
developed for the LSS that runs under |! NS 8 
Windows NT and Windows 95/98 operating E N m ETE | 
MM CFIPER DP VID S. 30H DOS 
    
   
     
UR 
  
  
AM od 
WR baad ¥en] M 
nie [1m 
JmapaDes ii 
system, see Figure 4. The software acts as a 
link between the user's commands from a 
   
  
PC-based machine and the LSS operating sig] eed 1 em Binden il iint. 
system and is used for scanning and TE Masesslbme: [ima oj 
acquiring the required images, Al-Hanbali Mer esta Vratéord Mun rind 
nt] a Imag: Dare 13003 i 
and Laurent (1995) and Al-Hanbali (1998). s 
7b uid [Veni] 
    
  
  
  
  
  
  
  
  
    
  
       
  
   
  
  
So EA eT HEEL | XET CAMERA] 
T€ CLEARS uj o wi 
The software handles various tasks. It sets GAMER | sur: nd) u wm 
and controls the various acquisition modes, : 
image dimension and resolution, field of GÓC; an sm 4 Vue M tan à 
. . fani inp E. lura lasrieRun — 5I? In^» 
view and the various camera parameters, tentés p | tnn e 
laser power, acquisition direction, focusing ehem + eu ise] reu] Deui] 
mode, and also controls the rotation stage cas | sewn aln | ae | € 
SCAN ELIO * PNE IRL H 
  
speed and acceleration. The software also 
sets up and initializes the LSS, synchronizes 
and acquires images, and transfers, retrieves Figure 4: The interface software platform 
and saves images between the LSS and the 
PC-based machine. 
   
  
  
  
3.2 Image Displaying, Processing and Digitization, Precise Edge Detection and Target Location and Surface 
Deformation representation Software: 
  
  
  
  
(b) 
Figure 5: (a) Platform of the image tools software: The intensity image and the depth coded image of the scanned 
mechanical test rig. (b) Platform of the image tools software: Introduced surface movement of the mechanical test rig. 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000. 11