Laser Triangulation Sensors

Both technologies use optical triangulation as their operating principle, but they solve fundamentally different measurement problems.

A laser triangulation sensor measures a single point. It returns one distance value per measurement cycle — the distance from the sensor to one spot on the object surface. This makes it the right tool for displacement, position, vibration, thickness, and level measurement, where you need fast, accurate data from a defined location.

A 2D laser scanner projects a full laser line rather than a point, simultaneously capturing hundreds or thousands of distance measurements across the object's cross-section. The output is a complete profile — shape, width, height, contour — rather than a single value. When the object or scanner moves, successive profiles combine into a 3D surface model.

The practical rule: if you need to know how far the surface is, use a laser triangulation sensor. If you need to know what shape the surface is, use a 2D laser scanner. For many production systems, both technologies are used together — triangulation sensors for fast point-based control, 2D scanners for geometry and profile verification.

The range of measurable parameters is broader than the name suggests. Riftek RF60x laser triangulation sensors are used for:

• Displacement and position — tracking the movement or position of a target relative to a fixed reference
• Dimensions — measuring the length, height, step, or thickness of components, including thin sheets and films
• Surface profile — building a 1D profile of a surface by scanning the sensor or moving the object
• Runout and vibration — detecting radial or axial runout of rotating parts, measuring vibration amplitude and frequency
• Sorting — detecting the presence, height, or position of objects on a conveyor for automated sorting
• Liquid and bulk material levels — non-contact level measurement in tanks, hoppers, and open containers
• Deformation — monitoring structural deflection or thermal expansion under load

The RF609 laser probe series extends this to inner diameter measurement of holes from 9 mm, making triangulation technology applicable to bore inspection tasks that standard external sensors cannot reach.

The RF60x line covers an exceptionally wide range — from 2 mm to 2,500 mm — distributed across specialized model series:

RF603 — the universal series. 26 models covering ranges from 2 mm to 1,250 mm. Linearity ±0.05% of range, sampling rate 9.4 kHz. Available with red or blue laser. The standard choice for most industrial measurement applications.

RF603HS — high-speed version of RF603. Same measurement ranges (2 mm to 1,250 mm) but with sampling rates up to 160 kHz. Designed for capturing fast events, vibration, and high-speed production processes.

RF602 — super compact sensors (39.5 × 30.5 × 17 mm, 40 g) for ranges from 10 mm to 500 mm. Linearity ±0.05%, sampling rate 9.4 kHz. Used where installation space is the primary constraint.

RF600 — large-base, long-range sensors covering 10 mm to 2,500 mm. Sensor body 170 × 61 × 31 mm, 500 g. Designed for remote measurement of large objects, hot surfaces, and outdoor applications.

RF609 / RF609Rt — laser probes for inner diameter measurement. Sensor body diameter from 9 mm, measuring holes from 9.2 mm to 48 mm in diameter. Accuracy ±2 µm.

RF60i — specialized sensors for pavement profile and road surface texture measurement. High solar radiation resistance, stable operation on wet surfaces, measurement frequency up to 70,000 Hz.

RF605 — compact sensors for ranges 50 mm to 500 mm. No longer recommended for new projects as this series is being phased out.

RF603 and RF603HS share the same housing, weight, and measurement ranges — from 2 mm to 1,250 mm — and are visually nearly identical. The key difference is sampling rate and the corresponding linearity specification.

RF603 measures at up to 9.4 kHz with linearity of ±0.05% of range. This is sufficient for the vast majority of industrial measurement tasks — dimensional control, displacement monitoring, level measurement, and profile scanning at standard production speeds.

RF603HS measures at up to 70 kHz — roughly 8 times faster — with linearity of ±0.1% of range at maximum speed. This makes it the right choice when the measurement target moves fast, vibrates, or when the event being captured is brief: high-speed extrusion lines, vibration analysis, road surface profiling from a moving vehicle, or any application where 9.4 kHz is insufficient to capture the dynamics of the process.

The trade-off is linearity: RF603HS at 70 kHz is rated at ±0.1% vs. ±0.05% for RF603. If your application does not require high speed, RF603 delivers better accuracy at lower cost.

The RF609 is a specialized laser probe designed for a task that standard external triangulation sensors cannot perform: measuring the inner diameter and geometry of holes, bores, and tubes from inside.

The probe body is cylindrical — 9 mm or 15 mm in diameter depending on the model — allowing it to be inserted into holes and measure the inner surface by rotating around the bore axis. It covers inner diameters from 9.2 mm to 48 mm with measurement accuracy of ±2 µm and a sampling rate of 9.4 kHz.

The RF609Rt variant includes a built-in slip ring, which allows continuous 360° rotation without cable winding — essential for fully automated inner diameter inspection integrated into production lines or CNC machines.

Use the RF609 when you need non-contact measurement of bore diameter, ovality, or inner surface profile — in applications such as precision machined holes, hydraulic cylinder bores, injector bodies, or any cylindrical cavity where an external sensor has no line of sight to the surface being measured.

Most RF60x sensors are available in both red (660 nm) and blue (405/450 nm) laser versions. The choice depends on the material and surface conditions of the measurement target.

Red laser (660 nm) is the standard option and performs well on the majority of industrial materials: metals, plastics, ceramics, painted surfaces, and machined parts. It is the right default choice unless the material presents a specific challenge.

Blue laser (405/450 nm) is recommended in three situations. First, for organic and semi-transparent materials — rubber, wood, food products, biological tissue — where a red laser penetrates below the surface and returns a diffuse, unstable signal. The shorter blue wavelength reflects cleanly from the surface layer without subsurface scattering. Second, for red-hot or incandescent metal surfaces, where the thermal emission spectrum overlaps with the red laser wavelength and degrades the signal-to-noise ratio; blue laser is far enough from the emission peak to remain stable. Third, for some translucent plastics and coatings where surface reflection with red laser is insufficient.

If your application involves any of these conditions, specify the BLUE option when ordering. For standard metallic and opaque surfaces in a factory environment, the red laser version is sufficient and typically more cost-effective.

RF60x sensors provide both digital and analog outputs, making them compatible with a wide range of industrial control systems and data acquisition equipment.

Digital interfaces:

• RS232 (up to 460.8 kbit/s)
• RS485 (up to 921.6 kbit/s)
• CAN V2.0B (up to 1 Mbit/s)
• Ethernet i

Analog outputs:

• 4–20 mA (load ≤ 500 Ω)
• 0–10 V

Additional I/O:

• Synchronization (trigger) input — CMOS/TTL, 2.4–5 V
• Programmable logic output — NPN, 100 mA max, 40 V max — configurable for range alarm, zero setting, mutual synchronization of multiple sensors, or hardware laser on/off control

For PLC integration, the analog output is the simplest path. For higher data rates or networked configurations, Ethernet and RS485 are the preferred options. The CAN interface is available for applications in automotive test environments or embedded systems where CAN buses are standard.

Interface type is specified at the time of ordering and is part of the model code.