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57 mm
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Edmund Optics 34 mm
Angle of DOF 5-15
15 15
3mm
2mm
8mm
Stock No. Price
Depth of Field Target #54-440 €670,00
(Y1, X1)
DOF 5-15 Depth of Field Target
428 +44 (0) 1904 788600 | Edmund Optics® N NEW PRODUCT NEW LOW PRICE
testing & detection targets illumination cameras imaging lenses microscopy lasers optomechanics optics
Substrate: Black on white-backed film
Construction: Aluminum
Maximum Depth: 50 mm
Dimensions: 57 H x 34 W x 57 mm D
Resolution: 5 and 15 lp/mm Scale
(both horizontal and vertical)
Dimensions: 110 x 110 x 110 mm
Pattern Size: 110 x 156 mm
Substrate: Black Print on White Mylar® with Protective Lamination
Low Mag Pattern (2 alternating frequencies):
1) 3 lines, 2 mm thick on 3 mm centers
2) 4 lines, 0,1 mm thick on 2 mm centers
Mid Mag Pattern: 20 lines, 0,1 mm thick on 0,5 mm centers
High Mag Pattern: 40 lines, 0,1 mm thick on 0,25 mm centers
Construction: Aluminum base
Magnification Range: 0,08X to 5X
TECHNICAL NOTE
This image (taken with an 8 mm focal length lens) demonstrates keystoning.
Clearly, the lines converge at the bottom of the image. The center location
of a line at the bottom of the image does not have the same center location
at the top of the image.
It is apparent that the blur in this image (taken
with a telecentric lens) is symmetric. If you take a
horizontal line profile across the image and find the
horizontal component of the center of each black
line, the location will be equal in the blurred part of
the image and the focused part of the image.
This difference in position can be converted to a degree of telecentricity with the following steps:
1) Find the distance between your top line profile and your bottom line profile, Y1 & Y2 ΔY = (Y1 - Y2)
2) Find the horizontal displacement (ΔX) of a target line: ΔX = |X1 - X2|
3) Calculate the telecentric angle: q = Tan-1(ΔX/ΔY)
lens
Line spread functions of ruling. Taken with VZM™ 200i at 1X PMAG.
Left: Iris Open. Right: Iris Half Open.
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DOF 5-15 Depth of Field Target
DOF at
15 lp/mm
DOF at
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EO Telecentricity Target
incidence
θ = 0˚
θ = 45˚
lp/mm
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Edmund Optics
®
®
110mm
156mm
10mm
4mm
Our telecentric target allows keystoning in an image to be visualized and accurately measured. The amount of keystoning is related to the telecentricity of
the lens that is imaging the target. The target is placed at a 45° angle to the optical axis so that the bottom of the target is further away from the lens than
the top of the target. When imaging the target through a non-telecentric lens, the distance between the vertical lines will appear to decrease at the bottom
of the image; this effect is known as keystoning. A perfectly telecentric lens will have no keystoning and the telecentricity will be 0°.
(Y2, X2)
Lens Mounted
at 45º Angle
Lens Mounted
Vertically
• Test Depth of Field in Imaging Systems
• Eliminates Need for Calculations
This unique target was developed to standardize an
area of optical tolerancing that is most commonly determined
theoretically. Our extensive experience in designing
optical systems has shown that depth of field
calculations can often yield very misleading results.
This target solves the problem and very accurately determines
the amount of shift an object can undertake
before producing an unacceptable image. The definition
of what constitutes an acceptable image is determined
by the user and the application.
The DOF 5-15 is made up of two sets of scales. Each,
when viewed at 45°, consists of horizontal and vertical
lines at a frequency of 5 and 15 line pairs per mm.
Instructions included.
• Critical Tool for Any Vision System Making Size or Distance Measurements
• Calibrates Any Type of Lens
• Covers Large Range of Magnifications
Telecentricity is an extremely useful metric for measuring the amount of perspective error inherent in an imaging
system. Determining the degree of telecentricity allows the user to calculate an imaging system’s maximum measurement
accuracy. The target can be used to calibrate the degree of telecentricity in both telecentric and non-telecentric
lenses. Keystoning becomes visual with the target and can be measured with software.
EO Telecentricity Target
Stock No. Price
EO Telecentricity Target #58-404 €984,00
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