spacer

Kalibriernormale, Objektmikrometer

Test Target

Partikelnormal / klein

Test Targets allow the calibration of measurement functions in microscopes through objects in different forms and sizes or of resolution of an optical system measured in Line Pairs per mm.

The Target allows the calibration of measurement functions in microscopes, to analyze particles and measured. A field of objects in different forms and sizes allow the user to check: rectangles, ellipsis, circles, rings and even fibre-shaped objects. To determine optical distortions there are three different sized arrays of cross-targets. The smallest Object is as small as 5μm.

For the calibration of the resolution (magnification) two scale bars in X and Y are applied in a corner of the target.



show moreshow less
Artikel Nr.
Beschreibung
043-102302-72
Particle Standard
download
Particle Standard for calibration and analyses
of microscopes and image analysing systems
-chrome structures on glas
-different structures in sizes (10ľm - 1025ľm)
- different shapes to verify the correct
calculation of structure parameters
-incl. Scale in x- and y-direction
- Dimension: 70x70x2mm
-Weight: 30gr
043-102302-75
download
Particle Standard for calibration and analyses
of microscopes and image analysing systems
-chrome structures on glas
-different structures in sizes (10ľm - 1025ľm)
- different shapes to verify the correct
calculation of structure parameters
-incl. Scale in x- and y-direction
- Dimension: 70x70x2mm
-Weight: 30gr
- Certification by DKD
- Scale calibrated with a national standard

Resolution Test Target

Auflösungs-Testtarget

Test targets (also called test charts, test samples or resolution test patterns) are used to determine the efficiency of optical systems. They are used to determine resolution, MTF, depth of field, distortion and telecentricity.

It is necessary to test and calibrate every single system for comparative measurements, especially when dealing with several measuring systems of the same type.


Stage micrometer

Objektmikrometer

The stage micrometer is a helpfull tool for calibration purposes (resolution, distortion, parfocality).

Stage micrometer 50mm 0.1 / 0.01 mm
- 50mm glass scale in 0.1 mm and 0.01 mm
- The calibration of surveying software


Image Quality Features

Resolution

The resolution of an optical system indicates the discernibility of two minute structures that can still be perceived separately. The resolution of optical instruments is limited by diffraction. The typical
specification is made in line pairs per mm (Lp/mm). The dependence of the resolution from the contrast describes the modulation transfer function.

 

Modulation Transfer Function (MTF)

MTF (also called contrast transfer function) describes the comparison of the contrast of the edges of a (real) object with the contrast of its image at a certain resolution (MTF = image contrast/object contrast). There will always be some contrast loss.

Contrast

The contrast describes the relationship between light and dark areas of an image, indicated in per cent (%).

 

Depth of Field

The depth of field (DOF), often erroneously dubbed “field of depth”) describes the expanse of the focussed area (within the object space) in front of and behind the optimal focus level. The smaller the aperture (i.e. the larger the f-number) the greater the depth of field area.
The hyperfocal distance is a special instance in which the depth of field area extends to infinity.
In case of telecentric lenses, the telecentric area is essentially the depth of field area.

 

Distortion

The distortion (or visual distortion) is a geometric image defect (aberration) of lens systems. It leads to different magnifications when the distance to the optical path of the system increases and creates the image of straight lines that do not cross the centre of the image to be reproduced in a bent way.

Decreasing magnifications (reductions) with respect to the image field edge are called barrel-shaped distortions (fish-eye effect) with an increasing pulvinate distortion. The distortion is generally indicated in per cent (%).

Member of
@
+49 89 898055 0
Please subscribe to our newsletter

Please choose the topics you are interessted in: