What is a telecentric lens?

A telecentric lens is designed so that chief rays enter (object-space telecentric), exit (image-space telecentric), or both (bi-telecentric) parallel to the optical axis. The result: magnification stays constant regardless of working-distance changes, eliminating the perspective error that makes standard lenses unreliable for dimensional measurement.

When do I actually need a telecentric lens?

When your measurement outputs numbers tied to geometry: gauging, thread and pitch checks, connector coplanarity, lead-span measurement. For appearance-only imaging such as color, presence, or texture, a standard FA or M12 lens is usually the better spend.

What does bi-telecentric mean?

Chief rays run parallel to the axis on both the object side and the image side: magnification constancy plus uniform illumination and response across the sensor. This is the metrology-grade configuration for gauging where every micron of repeatability is budgeted.

Why are telecentric lenses so large?

The front objective must be at least as large as the field of view it watches, so a 110 mm field needs a 110 mm-class front diameter. Size scales with field of view, not with focal length, which is why the low-magnification models in our table carry the largest barrels.

Can a telecentric lens also autofocus?

Yes. The YT series integrates an electrowetting liquid lens inside the telecentric path: focus steps in 20 ms, Z-axis stacking of 10-30 frames, and zero mechanical wear, so height-varying parts are measured in one station without motorized Z travel.

Which magnification should I choose?

Match magnification to field of view and sensor: 0.23X for wide fields at 145-200 mm working distance, 0.4X-0.5X for general gauging, 1X-1.75X for classic mid-range metrology, and 3X-4X for fine features at close working distance. Send the gauging task and we size it against the YT series and the 52-model LMJJ catalog, then return the matching spec sheet.

How do trigger and interface options work on the YT series?

Catalog models offer either software trigger with a micro USB interface (L / L4 suffixes) or hardware trigger with an aviation-grade connector (Y / Y2 suffixes); C-suffix models ship with the aviation connector. This maps to how your line clocks each inspection station.

How do you verify telecentricity and distortion?

Every YT prescription is released against design values, and production lenses are measured on metrology-grade instruments including Trioptics-class centration and laser Fizeau interferometry. Distortion is measured across the field, compared to design, and reported per batch.

Can you build a custom telecentric lens?

Yes. Custom telecentric designs are a standing capability, from prescription to per-batch verified production: 60 working days prototype to mass production, 30 days on repeat orders, under NDA with tooling stored free for five years.

What are the lead time and commercial terms?

Catalog YT models follow standard sampling terms with low MOQ; custom variants run 60 working days from prototype to mass production and 30 days on repeat orders. Commercial terms: 50% deposit, 50% before shipment.

Telecentric Series — Measurement-Grade Optics

Telecentric Lenses That
Keep Magnification Honest

0.14X to 6X, 24 catalog models across the LMJJ telecentric series — coaxial (TC), non-coaxial (TL) and bi-telecentric (BTC/BTL) types for 2/3", 1" and 1.1" sensors — verified telecentricity and distortion against design, with test records available per batch. Selected models integrate an electrowetting liquid lens for 20 ms focus response and Z-stack depth of field.

24 TC / TL / BTC0.14X–6X catalog

20 msliquid focus

Multi-frame Z-stacking

Per-batchtelecentricity & distortion records

ISO 9001certified

Lensmind machine vision lens for industrial automation

Official specification sheet

Twenty-four telecentric models. Every number on one page.

Twenty-four official telecentric models across 2/3″, 1″ and 1.1″ sensors — coaxial (TC), non-coaxial (TL) and bi-telecentric (BTC) types. Pick a model from the list — the page jumps straight to its row.

Lensmind bi-telecentric lens with coaxial illumination for machine vision measurement

Lensmind bi-telecentric lens without coaxial illumination

Lensmind telecentric lens with coaxial illumination port

Lensmind telecentric lens, object-space telecentric design for measurement

Sensor 2/3″ 11 models

Part NO.	Mag (x)	Type	Object FOV	WD (mm)	FNO.	Telecentricity	Distortion	Mount
LMJJ-BTC0.3X110N23	0.3	Coaxial Telecentric Lens	28×23.6	110	5.5	<0.1°	<0.05%	C
LMJJ-TL0.4X110N23(D44)	0.4	Non-Coaxial Telecentric Lens	22×16	110	6.5	<0.12°	<0.01%	C
LMJJ-TC0.5X110N23(D35)	0.5	Coaxial Telecentric Lens	17.6×12.8	109.6	9.6	<0.08°	<0.05%	C
LMJJ-TL0.5X110N23(D35)	0.5	Non-Coaxial Telecentric Lens	17.6×12.8	111.2	9.6	<0.08°	<0.05%	C
LMJJ-TC0.8X110N23	0.8	Coaxial Telecentric Lens	11×8	109	8	<0.1°	<0.06%	C
LMJJ-TL0.8X110N23	0.8	Non-Coaxial Telecentric Lens	11×8	109	8	<0.1°	<0.07%	C
LMJJ-TC1.2X107N23	1.2	Coaxial Telecentric Lens	7.3×5.3	107	10	<0.1°	<0.05%	C
LMJJ-TL1.2X107N23	1.2	Non-Coaxial Telecentric Lens	7.3×5.3	107	10	<0.1°	<0.05%	C
LMJJ-TC1.5X110N23	1.5	Coaxial Telecentric Lens	5.8×4.2	107	13	<0.1°	<0.05%	C
LMJJ-TL1.5X110N23	1.5	Non-Coaxial Telecentric Lens	5.8×4.2	107	13	<0.1°	<0.05%	C
LMJJ-TC1X110N23	1	Coaxial Telecentric Lens	8.8×6.4	110.9	10	<0.15°	<0.05%	C

Sensor 1″ 2 models

Part NO.	Mag (x)	Type	Object FOV	WD (mm)	FNO.	Telecentricity	Distortion	Mount
LMJJ-TC0.7X107N1	0.7	Coaxial Telecentric Lens	22.86	107.2	7	<0.1°	<0.05%	C
LMJJ-TL0.7X107N1	0.7	Non-Coaxial Telecentric Lens	22.86	107.2	7	<0.1°	<0.05%	C

Sensor 1.1″ 11 models

Part NO.	Mag (x)	Type	Object FOV	WD (mm)	FNO.	Telecentricity	Distortion	Mount
LMJJ-TC0.8X110N1.1	0.8	Coaxial Telecentric Lens	17.5×12.8	110	7.5	<0.1°	<0.02%	C
LMJJ-TL0.8X110N1.1	0.8	Non-Coaxial Telecentric Lens	17.5×12.8	110	7.5	<0.1°	<0.02%	C
LMJJ-TC1.5X110N1.1	1.5	Coaxial Telecentric Lens	9.5×6.9	110	11.5	<0.1°	<0.05%	C
LMJJ-TL1.5X110N1.1	1.5	Non-Coaxial Telecentric Lens	9.5×6.9	110	11.5	<0.1°	<0.05%	C
LMJJ-TC1X110N1.1	1	Coaxial Telecentric Lens	14.2×10.4	110	10	<0.1°	<0.05%	C
LMJJ-TL1X110N1.1	1	Non-Coaxial Telecentric Lens	14.2×10.4	110	10	<0.1°	<0.05%	C
LMJJ-TC3X65N1.1-GL	3	Coaxial Telecentric Lens	4.7×3.4	65	9.5-16	<0.2°	<0.05%	C
LMJJ-TL3X65N1.1-GL	3	Non-Coaxial Telecentric Lens	4.7×3.4	65	9.5-16	<0.2°	<0.05%	C
LMJJ-TL4X65N1.1(D44)	4	Non-Coaxial Telecentric Lens	3.5×2.5	65	12	<0.15°	<0.05%	C
LMJJ-TC4X65N1.1-GL	4	Coaxial Telecentric Lens	3.5×2.5	65	12-36	<0.15°	<0.05%	C
LMJJ-TC0.6X110N1.1(D44)	1.6	Coaxial Telecentric Lens	23.3×17.2	111	7.5	<0.04°	<0.03%	C

Lensmind Lab & Factory

Measured, Not Claimed — Data from Our Lab

Every claim on this page is backed by measurement. Below: the metrology instruments in our quality lab, optical bench and Zemax simulation records, and the production floor that builds and signs off every batch.

Metrology instruments