CCD Laser Displacement Sensor

LK series

This model has been discontinued.
Compliance with the certification standard is ensured as of the time of shipment from our company.

Recommended Replaceable Products: Confocal Displacement Sensor - CL-3000 series

Sensor Head, Small Spot, Laser Class 2 LK-503

LK-503 - Sensor Head, Small Spot, Laser Class 2

*Please note that accessories depicted in the image are for illustrative purposes only and may not be included with the product.

  • CE Marking





Sensor head Long-distance *1 Sensor head

Measurement mode

High-precision mode,Long-range mode

Reference distance

350 mm (High-precision mode),500 mm (Long-range mode)

Measuring range

±100 mm (High-precision mode),±250 mm (Long-range mode)

Light source


Visible red semiconductor laser


690 nm


0.95 mW

Laser Class

Part 1040.10

Class 2 Laser Product


IEC 60825-1

Spot diameter (at standard distance)

Approx. 0.7 mm (High-precision mode),Approx. 0.3 mm (Long-range mode)


±0.1% of F.S. *2


10 µm*3 (High-precision mode), 50 µm*3 (Long-range mode)

Analogue output

Output voltage

±10 V (10 µm/mV)*4 (High-precision mode), ±5 V (50 µm/mV)*4 (Long-range mode)


100 Ω

Output current

4 to 20 mA (Applicable load: 350 Ω max.)

Alarm output

NPN: 100 mA max. (40 V max.) (N.C.), Residual voltage: 1 V max.

Sampling cycle

1,024 µs

Other functions

Auto-zero, analog output holding when an alarm occurs, gain switching, response switching, span and shift adjustment of mirror surface measurement mode, changing the sampling cycle

Temperature characteristics

0.02% of F.S./°C


Power voltage

24 VDC ±10 %, Ripple (P-P) 10 % or less

Maximum current consumption

400 mA max.

Environmental resistance

Enclosure rating


Ambient light

Incandescent or fl uorescent lamp: 10,000 lux max.

Ambient temperature

0 to +50 °C (No condensation)

Relative humidity

35 to 85 % RH (No condensation)

Vibration resistance

10 to 55 Hz, Double amplitude 1.5 mm, 2 hours in each of the X, Y, and Z directions


Aluminium die-cast


Approx. 700 g (including cable)

*1 The LK-503 can both be used in High-precision mode or Long-range mode.
*2 Linearity was obtained using KEYENCE's standard target (Zirconia block gauge: LK-031/036, LK-081/086, LK-011, White ceramic block gauge: LK-501/503).
*3 Repeatability was obtained using KEYENCE's analogue sensor controller (RD-50) with the number of averaging measurements set to 64.
Note: The ripple of the analogue output may be 1 mV or more due to co mmon mode noise when observed with an oscilloscope or a high-speed A/D conversion board.
*4 When measurement is impossible, 12 V (31.2 mA) is output.

Data Sheet (PDF) Other Models