Frequently asked questions

Measuring Instrument Questions

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Measuring Instruments
  LC Series Laser Displacement meter
LK Series CCD Laser Displacement Meter
LK-2500 Series Long distance Laser Displacement Meter
LT Series Confocal Displacement Meter
LS-3100 Series Laser Scan Micrometer
LS-5000 Series HS Laser Scan Micrometer
LX2-V Series laser Through Beam Sensor
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LC Series
1. How does the LC measure?

The LC measures using the concept of triangulation. A laser diode shines a beam of light at the target. The light will diffuse off of the surface back toward the LC. This returning light is focused onto a Position Sensitive Device (PSD). The PSD measures the target distance by calculating the center of the returning spot.
If the target moves away from the sensor, the returning spot will move toward one end of the PSD. If the target moves toward the sensor, the returning spot will move toward the other end of the PSD. The position of the spot is proportional to the distance to the target.


2. What outputs come standard on the LC-2400A?

Analog voltage (+/- 10V DC)
Control I/O (NPN transistors: Near, Far, Alarm, High, Low, Go, Auto-Zero, Program select)
RS-232C (25-pin)

3. What optional outputs can be added to the LC-2400A?

Digital I/O 16-bit two's complement binary output of the measured data.
GP-IB General Purpose - Interface Bus: Up to 15 devices can be connected to a computer.

4. Which sensor heads can be used on specular (mirrored) targets?

LC-2420 10mm +/-0.2mm range [0.393 +/- 0.008 inch]
LC-2430 30mm +/-0.5mm range [1.181 +/- 0.019 inch]

5. Which sensor heads can be used on diffuse (non-mirrored) targets?

LC-2440 30mm +/-3mm range [1.181 +/- 0.118 inch]
LC-2450 50mm +/-8mm range [1.969 +/- 0.315 inch]

6. How many sensor heads can be connected to an LC-2400A?

Up to two heads can be connected to the LC for X+Y or X-Y measurements.

7. What measurement modes are available?

Normal (continuous), Peak (highest point held), Bottom (lowest point held), Peak-to-Peak (variation held)

8. What is "Resolution"?

Resolution is the smallest detectable change in distance.

9. What is "Linearity"?

Linearity is the amount of error that the measurement could contain as the target moves through the measuring range.

10. What is the standard target for the LC sensor heads?

LC-2420/2430: Mirrored target
LC-2440/2450: white diffuse-reflective object



LK Series

1. How does the LK series measure?

The LK series measures using triangulation. A laser diode shines a beam of light to the target. The light will diffuse off the surface and back to the sensor. The light is focused onto a CCD (Charge Coupled Device) detector. As the target moves away from the sensor, the focused spot will move toward one end of the CCD. As the target moves toward the sensor, the focused spot will move toward the other end of the CCD. The position of the laser spot on the CCD is directly proportional to the distance to the target.

2. What is LFTC?

The stands for Laser Flash Time Control. This circuit automatically adjusts the pulse time of the LK to compensate for target surface variations. The pulse time varies between 3.2us and 480us. As the target surface becomes darker, the LFTC increases the pulse time which increases the laser brightness.

3. What do the colors indicate on the stability indicator LED?

Red = Out of the measuring range - Alarm output
Yellow = In the measuring range - Measurement output
Green = In the center of the measuring range - Measurement output

4. Why is a CCD more stable than a PSD (Position Sensitive Device)?

The PSD uses the light distribution of the entire returned beam spot to determine the center of the spot. As the target surface changes, the distribution of the light changes. The light quantity of each CCD pixel is measured and the center of the spot is therefore detected. This allows a more stable measurement than a PSD.

5. What is the size of the laser spot?

Sensor Near Center Far
LK-031 250um 30um 250um
LK-081 350um 70um 350um

6. What voltage do we get from the LK?

+/- 5V DC (measuring), +12V (alarm)

7. Is there any way to disable the +12V alarm?

The alarm can be disabled by selecting the Analog Hold function.

8. How long can the sensor/controller cable be extended?

35m (using LK-C2, LK-C5, and LK-C10 cables)

9. What is the sampling time for the LK units?

LK-031 = 512us
LK-081 = 1024us

10. What response speeds can be selected?

Low speed = Averaging of 8 (8x512us)
High speed = Average of 1 (1x512us) (LK-031)


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LK 2500 Series

1. Does the LK-503 measure between 250 to 750mm or between 250 to 450mm?
The LK-503 has two measuring modes: Long Range and High Precision.

2. How do you change between these modes?
Simply press the "SHIFT- (up arrow)" button when you turn on the power key. Every time you press this combination, the LK toggles between the modes.

3. How can we check which mode we are in?
Press the ZERO/RESET and SPAN/RESET buttons at the same time. Five lights will appear for Long Range mode, three lights will appear for High Precision mode.

4. What type of output can I expect from each of the modes?
In Long Range mode, we get +/-5V for a measuring range of +/-250mm. (50mm/V)
In High Precision mode, we get +/-10V for a measuring range of +/-100mm. (10mm/V)

5. What steps are required to setup an LK-503?
Place the target at 500mm(350mm) from the LK. Press the ZERO button. Use the SHIFT-(up arrow) and SHIFT-(down arrow) buttons to adjust the analog output to 0V.
Now move the target to the end of the measuring range: 750mm (450mm). Use the SPAN-(up arrow) and SPAN-(down arrow) buttons to adjust the voltage output to be +5V (+10V). The LK is now set up.

6. How can I mount the LK-503 to a camera tripod?
OP-32682 is an L-Bracket with a ¼-20UNC connector for camera tripods.

7. Can the LK be used on shiny/mirrored targets?
Yes, simply tilt the head 4°-5° for mirrored targets.

8. Can the LK measure through a glass window? (high-temperature targets)
Yes, the LK is able to measure through a glass window. Keep the glass as thin and as close to the LK head as possible. Make sure to adjust the SHIFT and SPAN after placing the glass in front of the LK.

9. What is the spot size of the LK?
At 250mm: 1.2mm (At 250mm: 1.2mm)
At 500mm: 0.3mm (At 350mm: 0.7mm)
At 750mm: 1.2mm (At 450mm: 0.4mm)

10. How much ambient light can the LK withstand?
The LK-503 can withstand up to 5000 lux.
The LK-501 can withstand up to 10,000 lux. (Class IIIb laser)

Note: The numbers in ( ) are for High Precision mode.


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LT Series

1. How does the LT detect the target?

The light is focused to a spot. When the target is positioned at that focal spot, the reflected light will also be focused back through a pin-hole in the receiver. This will generate a trigger pulse to take a measurement.

2. How does the LT Measure?

The LT is called an Active Confocal sensor because its focusing lens is connected to a tuning fork. This fork is constantly scanning the lens up and down throughout the measuring range. Every time the lens is focused onto the target surface, the pin-hole will generate a trigger pulse. The LT will then take a measurement of the tuning fork position. Since we know the position of the fork, we know the position of the lens, and therefore, we know the position of the target.

3. How much does the spot size change on the LT?

Since the lens is moving, the spot is the same throughout the range. (LT8010=2mm, LT-8110=7mm)

4. What measuring modes are available?

Mode Purpose
Peak, Bottom, Peak-to-Peak Various holding modes.
Distance Height of a surface.
Thickness Thickness of a clear target
A.Hold (Automatic-Peak Hold) Used with pin/wire co-planarity.

5. How does Thickness mode work?

Thickness mode measures the distance between the top and bottom of a clear-coat or transparent object. As the LT scans the target, two triggers will occur; one for the top and one for the bottom. Thickness mode measures this distance and compensates for the specific Index of Refraction of the material.

6. What is the Index of Refraction?

The Index of Refraction occurs whenever light travels through a clear surface. For example, on a clear 1mm thick glass microscope slide, the measurement will be 0.667mm. After entering the index value, the measurement will be corrected to 1.0mm. The Index can either be entered into the LT directly, or it can be calculated from a target of known thickness.

7. How does A.Hold mode work?

Automatic-peak Hold mode holds the highest point on a connector pin or bonding wire. It resets the peak after each wire passes the sensor.

8. Can I connect the LT to a TV ?

The LT has a standard video output. This can be connected to the video input on a VCR and some TVs. It can not be connected to the coaxial antenna connector on a TV.

9. What outputs come standard on an LT?

Analog Voltage, High/Go/Low output transistors (NPN), RS-232C

10. How long can the Sensor-to-controller cables be extended to?

The LT comes with either 3m or 10m cables.


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LS-3100 Series

1. How does the LS measure?

The LS shines a laser beam off of a 8 sided mirror. As the mirror rotates, the beam scans down the window between the Transmitter and Receiver heads. If there is a target in the beam, the beam will be eclipsed by the target and the receiver will see darkness. The LS calculates the time that the beam is eclipsed by the target in order to measure the size of the target.

2. What measurement modes are available on the LS?

Diameter: Measures the outer diameter of a target.
Top Edge: Measures the distance from the top of the LS beam to the top of the target.
Bottom Edge: Measures the distance from the bottom of the LS beam to the bottom of the target.
Segment: Measures the distance between two target edges. (Inner diameter of a bearing.)

3. What is the maximum number of edges that can be placed in the LS beam?

126 edges (63 targets!)

4. How many sensor heads can be connected to the LS.

Two heads can be connected for independent measurement or a combination (X+Y, X-Y, etc.)

5. What holding modes are available?

Peak, Bottom, Peak-to-Peak

6. What outputs are standard on the LS?

Analog (+/-6V), RS-232C, Control I/O transistors (NPN and Relay)

7. What outputs can be special ordered?

BCD (NPN), GP-IB, Second Analog output

8. What is the maximum sensor-to-controller cable length?

10m (LS-3034 & 3033SO), 30m (LS-3032, 3033, 3036, 3060)

9. What is the maximum Transmitter-to-Receiver cable length?

3m max

10. What units does the LS display the measurement in?

Inches or mm


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LS-5000 Series

1. What measuring modes are available?

Diameter: Measures the outer diameter of a target.
Top Edge: Measures the distance from the top of the LS beam to the top of the target.
Bottom Edge: Measures the distance from the bottom of the LS beam to the bottom of the target.
Segment: Measures the distance between two target edges. (Inner diameter of a bearing.)
Pitch: Measures the pin-to-pin spacing on connector pins and outputs the min and max spaces

2. What is Pitch mode?

Pitch mode is used to check the spacing between the pins on a connector. The nominal spacing, number of pins, and +/- tolerance is entered into the LS. The LS then calculates all of the pin spacings and outputs the minimum and maximum spaces. The part can be rejected using the NPN transistor outputs.

3. How many sensor heads can be attached to the LS?

Up to 4 sets can be attached. Each head comes with a calibrated ROM card. This allows the operator to install additional heads at a later date.

4. How many analog outputs and Control I/O are available?

The LS-B11 board has two sets of analog output and Control I/O. Up to two boards can be installed by the customer in the LS.

5. What control units are available?

LS-5501 Desk-top control unit with built-in touch-panel control.
LS-5001 Controller with Windows 95 setup software.
LS-5001 & LS-D501 Controller with a separate panel-mount touch-panel control. (LS-D501)

6. What cable extensions are available between the LS sensors and the LS controller?

3m (LS-C3), 10m (LS-C10), 50m (LS-C50)

7. What cable extensions are available between the transmitter and receiver?

3m (OP-26540), 10m (OP-26816)

8. What is the wiring diagram for the RS-232C cable?

RJ-11 connector   9-pin connector
Pin 3------ --------- Pin 3
Pin 4------ --------- Pin 5
Pin 5------ --------- Pin 2
    Pin 4 jumped to Pin 6
    Pin 7 jumped to Pin 8
  OR  
RJ-11 connector   25-pin connector
Pin 3------ --------- Pin 2
Pin 4------ --------- Pin 7
Pin 5------ --------- Pin 3
    Pin 4 jumped to Pin 5
    Pin 6 jumped to Pin 20
     
rj-11 pinout diagram

 


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LX2-V Series

1 What is the sampling rate of the LX2-V10W?
The sampling rate is 12500 times/second.

2 What is the response time of the LX2-V10W?
The response time is 0.16 ms.

3 What is the resolution of the LX2-V10W?
The resolution of the LX2-V10W is 5mm with the LX2-11/12 and 10mm with the LX2-13.

4 What is the laser emission cycle of the sensor head?
The laser emission cycle is 80 us.

5 What is the maximum response frequency?
The maximum response frequency is 1kHZ.

6 What is the display update cycle?
The update cycle for the display is approximately 20 cycles/second.

7 What method of averaging the LX2-V10W uses?
The LX2-V10W uses the moving average.

8 What is the analog resolution of the LX2-V10W?
The analog resolution of the LX2-V10W is 3mW.

9 What is the linearity of the LX2 series with LX2-V10W?
· LX2-11: 2%
· LX2-12: 2%
· LX2-13: 3%

10 What is the laser class of the LX2-13?
The laser class of the LX2-13 is now FDA Class I.

11 How long should the unit warm up for the initial set up?
After supplying power, leave the LX2-V10W for 30 minutes before using it.

12 Is the output ON or OFF when you are setting the tolerance limits?
The outputs are disabled while you are setting the tolerance limits. However,
if an output is already ON before the LX2-V10W enter the tolerance setting mode, the output is retained.

13 What is the offset range?
The offset value can be set within the range of +/- 19.999.

14 What happens when the number of the displayed digits is set to four, the tolerance
limits are displayed with 5 digits?

The actual measured value, rather than the displayed value, is used for comparison with the tolerance limits.

15 What happens when the auto zero fuction is activated when an offset value is set?
When an offset value is set, the offset value is displayed when the auto zero
function is activated.

16 What is the analog resolution of the LX2-V10W in (mV)?
The analog resolution of the LX2-V10W is 3mV.

17 What is the main function of the Auto Scaling funtion?
The main function is to set up the display to measurement as a percentage, voltage, mm or inch.

18 What is the difference between LX2-70 & LX2-V10 analog voltage output?
LX2-70: 1-5 Volts
LX2-V10: 0-5 Volts Analog voltage proportional to the displayed value can be output.

19 Does we need to buy a switch in other to use the auto peak function?
No, the auto peak(bottom) hold function allows the detection of a target passing through the optical axis without a sensor for synchronization.

20 What is the differences between LX2-70 & LX2-V10 output terminals?
LX2-70: HI & LO (2 outputs)
LX2-V10: HI. GO & LO (3 outputs)


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