Machine Vision Telecentric Lenses
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Normal machine vision lenses exhibit varying magnification for objects at different distances from the lens. This causes several problems for machine vision error proofing and other applications:

the apparent size of objects changes with distance from the camera
some features or objects may be hidden by objects that are closer to the lens
the apparent shape of objects varies with distance from the center of the field of view (FOV). Objects appearing close to the edges are viewed from an angle, while objects near the centre of the FOV are viewed frontally (circles near the centre of the FOV become ellipses when moved towards the periphery).

Telecentric lenses, on the other hand, have the same magnification at all distances. An object-space telecentric lens creates images of the same size for objects at any distance and has constant angle of view across the entire field of view. An object that is too close or too far from the lens may still be out of focus, but the resulting blurry image will be the same size as the correctly-focused image would be.

Because their images have constant magnification and geometry, telecentric lenses are often used for metrology applications (among other applications), when a machine vision system must determine the precise size of objects independently from their position within the FOV and even when their distance is affected by some degree of unknown variations. These lenses are also commonly used in optical lithography, for forming patterns in semiconductor chips.

Navitar offers a family of high-performance telecentric lenses for use in machine vision, metrology, and precision gauging applications. All provide low optical distortion and a high degree of telecentricity for maximum, accurate image reproduction, particularly when viewing three-dimensional objects.

One of the most important benefits of a telecentric lens is that image magnification does not change as object distance varies. A telecentric lens views and displays the entire object from the same prospective angle, therefore, three-dimensional features will not exhibit the perspective distortion and image position errors present when using a standard lens. Objects inside deep holes are visible throughout the field, undistorted, therefore, telecentric lenses are extremely useful for inspecting three-dimensional objects or scenes where image size and shape accuracy are critical

Our machine vision lenses include the 12X Telecentric Zoom lens, TC-5028 telecentric video lens, Invarigon-R™, Macro Invaritar™, ELWD Macro Invaritar™, and Invaritar Large Field telecentric lenses. Click on the links to the left to view specific lens information. Then, select the telecentric lens that will provide you with the best image possible for your machine vision, gauging, or inspection requirements. If you need further technical assistance or information, please contact us. Our application engineers will be happy to assist you every step of the way in selecting the lens that is perfect for your application.

Specifications:

Mag.	Telecentric Error (degrees)			Object N.A.	Image N.A	Object Depth of Focus (mm)	Telecentric Error (mm)			Object Size			Approx. MTF (Ip/mm)	Resolvable Features (microns)
Mag.	1/4" Format	1/3" Format	1/2" Format	Object N.A.	Image N.A	Object Depth of Focus (mm)	1/4" Format	1/3" Format	1/2" Format	1/4" Format	1/3" Format	1/2" Format	Approx. MTF (Ip/mm)	Resolvable Features (microns)
0.16	0.05	0.06	-0.03	0.005	0.032	38.8	0.018	0.020	-0.009	25.0	37.3	49.7	15	33
0.23	-0.10	-0.09	-0.18	0.007	0.031	19.4	-0.017	-0.016	-0.030	17.4	26.1	34.8	22	23
0.33	-0.19	-0.18	-0.27	0.010	0.030	10.3	-0.016	-0.016	-0.024	12.1	18.2	24.3	30	17
0.47	-0.23	-0.23	-0.31	0.013	0.028	6.0	-0.012	-0.012	-0.016	8.5	12.8	17.0	39	13
0.67	-0.25	-0.25	-0.34	0.016	0.024	3.8	-0.008	-0.008	-0.011	5.9	8.9	11.9	49	10
0.96	-0.27	-0.27	-0.36	0.020	0.021	2.6	-0.006	-0.006	-0.008	4.2	6.3	8.4	59	8
1.36	-0.29	-0.29	-0.38	0.024	0.017	1.8	-0.004	-0.005	-0.006	2.9	4.4	5.9	71	7
1.94	-0.25	-0.24	-0.29	0.028	0.015	1.3	-0.003	-0.003	-0.003	2.1	3.1	4.1	84	6
Distortion < 0.1% for all magnifications. Working Distance = 188 mm for all magnifications.

Additional Resources:

For further information, please peruse through Navitar's Telecentric Lens Brochure (PDF).

Available Options Below. Call us or e-mail us for custom options.
12X Telecentric:
C-Mount Invaritar Large-Field Base Lenses:
CCTV Telecentric:
ELWD Macro Invaritar Telecentric Lenses:
F-Mount Invaritar Large-Field Base Lenses:
Fiber Bundle Collimator:	($665.00)
Invarigon-R Telecentric Lenses:
Invaritar Large-Field Attachment Lenses:
Macro Invaritar Telecentric Lenses:
Mounting Brackets:
Right Angle Attachments:
Teleconverters & Adapters:

Quantity:

Machine Vision Telecentric Lenses[nvtcnlns]

Specifications:

Additional Resources:

Machine Vision Telecentric Lenses
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