Depth from Focus
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+ | =Depth from Focus= | ||
+ | ==3D surface metrology== | ||
+ | * In principle it should work with any microscope, which has a motorized z-drive and a CCD camera (see [[Mimas Video Input|Mimas video input]]). | ||
+ | * The results will be even better, if the illumination optics of the microscope can project a pattern. | ||
+ | * Non-destructive measurement of surface profiles | ||
+ | * Vertical resolution <math>30\ \mu m</math> and better (depending on aperture-size, magnification, projection-pattern and the surface properties of the object). | ||
+ | * Lateral resolution <math>25\ \mu m</math> and better (depends). | ||
+ | * Captured area about <math>0.5\ mm^2</math> (can be improved by using a motorized X-Y-table and stitching software). | ||
+ | * '''Open Source''' (you are free to improve the code yourself and redistribute it). | ||
+ | |||
+ | ==Demonstration== | ||
Here are some typical microscope images (showing a surface, which has been [http://www.twi.co.uk/j32k/unprotected/band_1/surfi-sculpt_index.html shaped using a power beam]). | Here are some typical microscope images (showing a surface, which has been [http://www.twi.co.uk/j32k/unprotected/band_1/surfi-sculpt_index.html shaped using a power beam]). | ||
{|align="center" | {|align="center" |
Revision as of 15:18, 2 February 2006
Contents |
Depth from Focus
3D surface metrology
- In principle it should work with any microscope, which has a motorized z-drive and a CCD camera (see Mimas video input).
- The results will be even better, if the illumination optics of the microscope can project a pattern.
- Non-destructive measurement of surface profiles
- Vertical resolution <math>30\ \mu m</math> and better (depending on aperture-size, magnification, projection-pattern and the surface properties of the object).
- Lateral resolution <math>25\ \mu m</math> and better (depends).
- Captured area about <math>0.5\ mm^2</math> (can be improved by using a motorized X-Y-table and stitching software).
- Open Source (you are free to improve the code yourself and redistribute it).
Demonstration
Here are some typical microscope images (showing a surface, which has been shaped using a power beam).
Using a focus-stack one can compute images with extended depth of focus:
If the surface can be illuminated properly, one can even do a 3D-reconstruction of the surface:
[[Image:suevit20.png | 200px|3D reconstruction of suevit (1.4MB video)]] |
As the idea for the algorithm was fixed already, it was possible to implement the algorithm as a command-line tool in less than 4 days, using existing Mimas-software (exspecially the operators for boost::multi_array).
As this is a "quick hack", there's still lots of space for improvements.
Links
- Anaglyph images
- german diploma thesis about depth of focus (also available as PDF)
- Mechrob-paper Focus set based reconstruction of micro-objects