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Multi-Purpose Digital Laser Sensor

LV-N series

LV-S31 Small Beam Spot Reflective

Small size and highly flexible installation

LV-S31: Unaffected by Targets' Colour

No readjustment needed for tooling change

Since the LV-S31 detects based on target height or position, and not colour, it will not have to be readjusted when the colour of a target changes.

LV-S31 Series Adjustable Distance Detecting Head Laser Sensor

Light receiving element: Dual Photodiode

Light receiving element: Dual Photodiode

Dual Photodiode

The dual photodiode (PD) receives the reflected beam spot from a target and focuses it onto the dual PD. By adjusting the trimmer, the reflected spot can be centred so that half of the spot is on the NEAR PD, and half is on the FAR PD for a 1:1 ratio. As the target moves closer to the head, the reflected beam spot shifts more toward the NEAR PD and the displayed value will decrease. As the target is moved away from the head, the spot shifts toward the FAR PD and the displayed value increases. By detecting based on distance and not brightness, the LV-S31 can be set to detect that a part is not only present, but that it is in the correct position, regardless of the surface colour.

Adjust setting to optimum conditions without relocating sensor - Adjustable Structure

You can adjust light receiving element to optimum conditions by simply rotating the adjustment trimmer.

Adjust setting to optimum conditions without relocating sensor - Adjustable Structure

Adjust setting with a sensor head

Adjust setting with a sensor head

The sensor head is equipped with an output indicator and position indicator that indicates the distance with a target. This makes it easy to adjust the settings online if the amplifier is not easily accessible or visible.

Distance - Hysteresis (Typical)

Hysteresis when the light receiving element and the setting value are adjusted to 5000 at each distance.

Distance - Hysteresis (Typical)

Colour canceling function

Colour canceling function

Dual photodiode and original algorithm correct colour influence of a target that is displaced from the centere.

Long-range gap detection

Long-range gap detection

The LV-S31 can detect a 0.04" (1 mm) gap at a distance of 7.87" (200 mm) and a 0.02" (0.5 mm) gap at a distance of 1.97" (50 mm). (Target: White paper, response speed: SPED4 at ambient temperature) *Maximum detecting distance varies according to target's reflectance



Detecting loose caps

Detecting loose caps


Detecting presence/absence of contents

Detecting presence/absence of contents








Small side view

Adjustable distance definite reflective

FDA (CDRH) Part 1040.10

Class 1 Laser Product

IEC 60825-1

Light source

Visible red semiconductor laser, Wavelength: 655 nm



600 mm

480 mm

50 to 200 mm
(Adjustment range)


500 mm

400 mm


400 mm

320 mm


300 mm

240 mm


200 mm

160 mm


150 mm

120 mm

Environmental resistance

Ambient temperature

-10 to +50 °C (No freezing)

0 to +50 °C (No freezing)



Glass reinforced plastic



Lens cover

Norbornene plastic


Transmitter lens: Norbornene plastic
Receiver lens cover: Polyarylate


Approx. 70 g

Approx. 75 g


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