DDSK Ultra-Miniature Laser Diffuse Reflective Sensor (M3/M4/M5/M6/M8)
Ultra-miniature M3-M8 threaded laser diffuse sensor, 650nm laser, no reflector, 10-30VDC, IP65.
🔍 Click to enlarge · 1/16Technical Specifications
| Type | Ultra-miniature laser diffuse reflective photoelectric switch |
|---|---|
| Light source | 650nm red laser |
| Detection method | Diffuse reflective |
| Detection distance | M3: 5-30 / 5-40mm; M4: 10-50 / 10-70mm; M5: 15-100 / 15-130mm; M6: 20-150 / 20-200mm; M8: 20-150 / 20-200mm |
| Output type | NPN / PNP, normally open NO (suffix 1) / normally closed NC (suffix 2) |
| Operating voltage | 10-30VDC |
| Thread size | M3 / M4 / M5 / M6 / M8 |
| Protection rating | IP65 |
Overview
The DDSK series is an ultra-miniature threaded-barrel laser diffuse reflective photoelectric sensor, available in M3, M4, M5, M6, and M8 thread sizes. It uses a 650nm red laser diode to detect objects directly, without a reflector, and is built for machine builders, OEM equipment integrators, and automation engineers who need to detect small or closely-spaced parts in installation spaces too tight for standard-size (M12/M18) sensors.
Each thread size offers two selectable detection-range variants, from 5-30mm (M3, short range) up to 20-200mm (M6/M8, long range), and every variant can be ordered as NPN or PNP output with normally-open (NO) or normally-closed (NC) switching logic. The sensor runs on a 10-30VDC supply and carries an IP65 protection rating.
Features & Benefits
Laser Spot for Precise Small-Target Detection
Using a 650nm laser diode instead of a standard infrared LED gives a small, well-defined light spot, which helps distinguish and detect small or narrow objects at the specified range.
No Reflector Required (Diffuse Reflective Design)
The sensor detects the target's own reflected light, eliminating the need to install and align a separate reflector, which simplifies installation in confined spaces.
Ultra-Miniature Threaded Body Fits Tight Mounting Spaces
Available in M3, M4, M5, M6, and M8 threaded barrels, allowing installation in machine locations too small for standard M12/M18 sensors.
Five Thread Sizes with Dual Detection-Range Options Each
Each thread size offers two selectable detection-distance ranges (e.g. M4: 10-50mm or 10-70mm), letting integrators match the sensor to their specific working distance without redesigning the mount.
Selectable NPN/PNP Output and NO/NC Logic
Each model is available as NPN or PNP, normally-open (NO) or normally-closed (NC), giving four output combinations per detection range to match different PLC/controller input requirements.
Wide-Range 10-30VDC Supply
Operates across a 10-30VDC input range, compatible with common industrial control voltages (12V/24V) without a dedicated power converter.
IP65-Rated Housing
The IP65 protection rating provides dust-tight sealing and protection against water jets, suitable for typical factory-floor environments with dust or occasional washdown spray.
Applications
Models & Ordering Information
M3 thread, 5-30mm detection range
M3 thread, 5-40mm detection range
M4 thread, 10-50mm detection range
M4 thread, 10-70mm detection range
M5 thread, 15-100mm detection range
M5 thread, 15-130mm detection range
M6 thread, 20-150mm detection range
M6 thread, 20-200mm detection range
M8 thread, 20-150mm detection range
M8 thread, 20-200mm detection range
How to Select
- Step 1 — Choose the thread size (M3, M4, M5, M6, or M8) based on the maximum size your mounting hole or bracket can accommodate; larger threads generally support longer detection ranges.
- Step 2 — Choose the detection-range variant for your thread size: M3 offers 5-30mm or 5-40mm; M4 offers 10-50mm or 10-70mm; M5 offers 15-100mm or 15-130mm; M6 offers 20-150mm or 20-200mm; M8 offers 20-150mm or 20-200mm.
- Choose NPN output if your PLC/controller input is sink-type (low-level trigger).
- Choose PNP output if your PLC/controller input is source-type (high-level trigger).
- Choose normally-open (NO, suffix 1) if you need the output to switch on when an object is detected.
- Choose normally-closed (NC, suffix 2) if you need the output to switch off when an object is detected.
- Assemble the full part number from thread size, range code, output type, and NO/NC logic — e.g. M4 thread, 10-70mm range, PNP, normally-open corresponds to DDSK-0470P1.
- Confirm that your supply voltage falls within 10-30VDC and that IP65 protection is sufficient for your installation environment; for continuous immersion or strong corrosion exposure beyond IP65, confirm suitability with the factory.
📘 Need the full method? NPN vs PNP Sensor Outputs Explained
When NOT to specify the DDSK — and what to use instead
A working distance past what the miniature body supports (e.g., beyond 200mm)
Why not: This ultra-miniature M3-M8 family tops out at 20-200mm on the M6/M8 threads; the smallest M3 thread only reaches 5-40mm.
Use instead: a standard M12/M18 laser diffuse or through-beam sensor for longer working distances
The target is dark, transparent, or low-reflectivity near the top of the stated range
Why not: As a diffuse reflective design it detects light bounced off the target's own surface, so the quoted mm ranges are reflectivity-dependent rather than a fixed distance for every object.
Use instead: a laser through-beam pair, which is far less sensitive to differences in target surface
Only one small thread size is available on the bracket, but a longer range than that size supports is required
Why not: Each thread size is tied to a fixed pair of range options (e.g., M4: 10-50mm or 10-70mm); range cannot be stretched within the same thread.
Use instead: step up to the next thread size (M6/M8) if the mounting hole can be enlarged
Personnel-safety guarding or access-point interlocking
Why not: Only IP65 sealing and a 10-30VDC supply rating are documented; the data contains no safety-function certification.
Use instead: a certified safety light curtain, kept entirely separate from this proximity sensor
Specifications we do not publish yet
We only publish a figure once we are confident it is true. The items below are still being validated through further testing and real-world customer feedback, so for now we would rather leave them open than guess. If one of them matters to your design, ask us for the latest validated status.
- Laser safety class (only 650nm wavelength is documented)
- Minimum detectable object size below the stated mm ranges
- Response time / switching frequency
- Hysteresis (repeat accuracy)
- MTBF
- Operating/storage temperature range
- Cable/connector specification
Frequently Asked Questions
What does "diffuse reflective" mean for this sensor?
Why use a laser diode instead of a standard infrared LED?
What thread sizes are available in the DDSK M-series diffuse sensor?
What detection distance does each thread size support?
Is the output NPN or PNP?
What is the supply voltage?
What is the sensor's protection (ingress) rating?
How do I read the part number, e.g. DDSK-0470P1?
Does this sensor require a reflector like a retro-reflective sensor?
Can you provide certification documents for the DDSK series?
Works Well Together
On the same machine or line, DDSK is typically ordered together with: Photoelectric Sensors · Fiber Optic Sensors · Slot Sensors
BGS-CX441 / BGS-CX442 Background Suppression Photoelectric Sensor
Wire-adjustable BGS sensor with 2 mm or 15 mm spot, 10-300 mm range, published black/white differential distance.
Fiber Amplifier (Digital Fiber Optic Sensor Amplifier)
Digital fiber optic amplifiers with NPN/PNP output, from potentiometer economy models to 25µs dual-display smart units.
DD-303N / DD-403N Wide-slot Photoelectric Sensor
13 mm through-beam slot sensor giving real tolerance for thick or fluttering parts, still detecting down to 2.2×0.5 mm.
Related Products in Laser Switch Sensors
DDSK Laser Diffuse Reflective Sensor M12 / DK Laser Diffuse Reflective Sensor M18
M12/M18 threaded laser diffuse reflective sensor with a visible 650nm red laser for fast alignment.
DS Laser Through-Beam Sensor M12/M18 (50m)
M12/M18 laser through-beam sensor pair, 50m range, NPN/PNP output, NO or NO+NC, IP65 rated.
DS Miniature Laser Through-Beam Sensor (M3/M4/M5/M6/M8)
Ultra-small M3-M8 laser through-beam sensor pair detects tiny parts up to 20-30m, NPN/PNP, NO/NC output.
DS Right-Angle (90°) Laser Through-Beam Switch M4 / M6
90° right-angle M4/M6 laser through-beam switch with a 1.5-2mm spot and 20m detection range for tight spaces.