Bilateral telecentric lenses for optical metrology

The bilateral telecentric lenses for matrix and line scan cameras set a new standard of lens performance for optical metrology. The absolute distortion in the image plane of these lenses is only a few micrometers.

The lenses can be focused on the image side in a range of ± 3 mm which means that the working distance can be adjusted within the defined limits without any change in the lens magnification. Thus the lenses can easily be adjusted to fit the space conditions in the application.

Due to the numeric aperture of 0.14 or 0.13, the light intensity of these lenses is considerably higher than of other available lenses. The integrated iris allows easy setting and locking for the demands of any measurement task.

All lenses have a lockable iris and focus adjustment.

Catalog

Technical details: Characteristics Accessories

Xenoplan 1:1	num. aperture	0.14
	magnification range	1 : 1
	telecentric depth	± 2
	distortion at image plane	< 0.1%
	working distance	47 ± 3 mm
	object size (½")	6.4 x 4.8 mm
	object size (2/3")	8.8 x 6.6 mm
	weight	1490 g
	code no.	35850
	opt./mech. data

Xenoplan 1:2	num. aperture	0.14
	magnification range	1:2
	telecentric depth	± 4
	distortion at image plane	< 0.7%
	working distance	195 ± 12 mm
	object size (½")	12.8 x 9.6 mm
	object size (2/3")	17.6 x 13.2 mm
	weight	2150 g
	code no.	35851
	opt./mech. data

Xenoplan 1:3	num. aperture>	0.14
	magnification range	1:3
	telecentric depth	± 6
	distortion at image plane	< 1.5%
	working distance	161 ± 27 mm
	object size (½")	19.2 x 14.4 mm
	object size (2/3")	26.4 x 19.8 mm
	weight	1600g
	code no.	35852
	opt./mech. data

Xenoplan 1:4	num. aperture	0.13
	magnification range	1:4
	telecentric depth	± 8
	distortion at image plane	< 0,5%
	working distance	176 ± 48 mm
	object size (½")	25.6 x 19.2 mm
	object size (2/3")	35.2 x 26.4 mm
	weight	2000g
	code no.	35853
	opt./mech. data

Xenoplan 1:5	num. aperture	0.13
	magnification range	1:5
	telecentric depth	± 10
	distortion at image plane	< 0.3%
	working distance	269 ± 75 mm
	object size (½")	32 x 24 mm
	object size (2/3")	44 x 33 mm
	weight	2600 g
	code no.	35854
	opt./mech. data

Characteristics of the bilateral telecentricity

In practice the measurement objects often have different distances to the lens flange, shown here O₁ and O₂ (Fig.1 ).

Fig. 1

Fig. 1 illustrates that with object sided telecentric lenses the image of O₂ in the sensor plane B₁ is asymmetrical which will cause measurement errors because of displacement of the edge position.

Fig. 2

Fig. 2 shows the symmetrical image of the object in the sensor plane with the bilateral telecentric lenses. In this case, the position of the object has no effect on edge detection, thus the measurement is more accurate.

More information about telecentricity: short and detailed

Accessories

Klemmstück für telezentrische Objektive Clamping device for easy fastening
of the lenses to the measurement system via 4 x M4 or 1 x ¼"
thread hole in the mounting flange.
Art.-Nr. 36378