Dot Lasers

Spot Lasers and Laser Modules for Industry and OEMs

Q: What do &bdquo;fixed focus&ldquo; and &bdquo;adjustable&ldquo; mean?

Fixed focus: the optics are set at the factory to a fixed distance and cannot be changed – typically a point in the range 1–5 m. Benefit: no accidental adjustment possible, stable over the entire service life. Trade-off: cannot be adapted to other distances. Adjustable: the optics sit in an adjustable brass ring at the front of the module and can be focused by the user to any desired distance (5 cm to infinity). After adjustment the optics are secured with thread-locking varnish in the thread. Which variant? Fixed focus for defined series production with constant distance, adjustable for flexible applications and one-off setups.

Q: Which typical applications exist for point lasers?

Industrial alignment: point lasers as a reference for aligning machines, conveyors, roller tracks and light barriers. Distance measurement: as a light source in triangulation sensors for distance and profile measurement. Marking: in research and test setups as precise reference points. Optical test setups: as a light source for beam splitting, diffraction and interference experiments. Workpiece positioning: in production as a reference point for drilling and placement operations. Construction: plumb points, height references, wall alignment (not our domain – we supply industrial quality, not DIY plumb lasers).

Q: Why does a green point laser look brighter than a red one?

The human retina is most sensitive in the green spectral range around 555 nm – that is the peak of the eye's spectral sensitivity. Green laser light at 520 nm sits close to this peak, while red light at 650 nm sits at the edge of visual sensitivity. Specifically: a 5 mW green point laser looks visually about as bright as a 25–35 mW red point laser. Practical effect: at equal perceived brightness, green gives you a lower laser class – Class 2 instead of Class 3R for red. This simplifies safety measures significantly. Trade-off: green laser diodes are more expensive and more temperature-sensitive than red ones.

Q: What is beam divergence and why does it matter?

Beam divergence describes how strongly a laser beam expands with distance. It is measured in milliradians (mrad). Example: a beam with 1 mrad divergence widens by 10 cm over 100 m distance. For point lasers low divergence is desirable – so the dot stays sharp over long distances. Typical values: 0.5–2 mrad after collimation. Influencing factors: emitter size of the laser diode, quality of the collimator optics, wavelength. For our OEM modules the divergence is typically specified in each module's datasheet or optimized at the factory.

Q: What do the laser classes 3R and 3B mean?

Class 3R: increased risk on direct viewing of the beam, but the natural blink reflex usually still provides sufficient protection. Safety goggles are recommended but not strictly required in all cases. Maximum 5 mW in the visible range. Class 3B: direct radiation is hazardous to the eye, but diffuse reflections are usually harmless. Safety goggles are mandatory in the open beam area. Beam enclosure where possible, clear marking of laser areas, training of personnel. Maximum 500 mW. Both classes require a laser safety officer in commercial use.

Q: When to choose a point, line or cross laser?

Point lasers (also called dot lasers) project a sharp spot of light – ideal for precise single-point marking, distance measurement, triangulation and alignment tasks over large distances. Benefit: all the optical power is concentrated at the point, giving very high visibility even at low power. Line lasers project a line – ideal for cutting lines, paths and boundaries. Cross lasers project a cross from two lines – ideal for centring and 2D alignment. Rule of thumb: point for „this spot here“, line for „along this axis“, cross for „centred exactly on this intersection“.

Dot lasers are compact laser modules that project a collimated beam as a single point. They are ready to run: laser diode in a cylindrical housing, screwed-in collimation optic, adjustable and universally usable – for component alignment, machine control, sensing, triangulation, material inspection and as a light source in optical systems.

Lasershop offers dot lasers in red (635 nm), green (520 nm) and blue (450 nm) as standard modules and in modulated versions with TTL or analogue modulation for pulsed operation and sensing. For higher supply voltages we provide matching step-down regulators. Built by MediaLas in Germany as a standard product or OEM variant.

31 Products

Diode laser module 1mW 650nm, adjustable focus

Variants from €22.61

€51.17

Diode laser module 5mW 650nm adjustable focus, with modulation input

Variants from €89.25

€104.15

Diode laser module 10mW 635 nm bright red, adjustable focus, modulation input

€113.05

Diode laser module 40mW 450nm BLUE, adjustable focus, insulated

€126.14

Diode laser module 5mW 635nm BRIGHT RED, adjustable focus

Variants from €21.42

€33.32

Diode laser module 5mW 650nm adjustable focus

Variants from €16.66

€45.22

Dot laser module 1mW 520nm GREEN, adjustable focus, optical stabilized, class II

Variants from €104.72

€127.93

Diode laser module 10mW 635nm BRIGHT RED, adjustable focus

Variants from €41.65

€56.55

Diode laser module 10mW 650nm, adjustable focus

Variants from €33.32

€48.22

Diode laser module 10mW 650nm, adjustable focus, modulation input

€101.15

Diode laser module 20mW 635 nm bright red, adjustable focus, modulation input - Kopie

Variants from €124.95

€139.85

Diode laser module 20mW 635nm BRIGHT RED, adjustable focus, insulated

Variants from €60.69

€87.49

Diode laser module 5mW 520nm GREEN, adjustable focus, insulated

Variants from €113.05

€141.61

Diode laser module 80mW 450nm BLUE adjustable focus

Variants from €152.32

€175.53

Diode laser module 10mW 520nm GREEN, adjustable focus, insulated

Variants from €123.76

€161.86

Diode laser module 25mW 520nm GREEN, adjustable focus, insulated

Variants from €159.46

€182.67

Diode laser module 30mW 650nm, adjustable focus

Variants from €47.60

€59.50

Diode laser module 100mW 650nm, adjustable focus

Variants from €64.26

€87.47

Diode laser module 30mW 650nm, adjustable focus, modulation input

€116.62

Diode laser module 40 mW 520nm GREEN, adjustable focus, insulated

Variants from €207.06

€245.16

Dot laser module RED, water sealed IP65, 60 mW

Variants from €154.70

€227.29

Diode laser module 60mW 650nm, adjustable focus, modulation input

Variants from €124.95

€139.85

Mounting block for 12mm line and cross laser modules

€14.87

Laser module mount for 12mm modules

€14.87

Frequently asked questions about dot lasers

Dot lasers in red, green and blue: frequently asked questions

Answers about color selection for industrial applications in our dot laser category.

What do „fixed focus“ and „adjustable“ mean?

Fixed focus: the optics are set at the factory to a fixed distance and cannot be changed – typically a point in the range 1–5 m. Benefit: no accidental adjustment possible, stable over the entire service life. Trade-off: cannot be adapted to other distances. Adjustable: the optics sit in an adjustable brass ring at the front of the module and can be focused by the user to any desired distance (5 cm to infinity). After adjustment the optics are secured with thread-locking varnish in the thread. Which variant? Fixed focus for defined series production with constant distance, adjustable for flexible applications and one-off setups.

Which typical applications exist for point lasers?

Industrial alignment: point lasers as a reference for aligning machines, conveyors, roller tracks and light barriers. Distance measurement: as a light source in triangulation sensors for distance and profile measurement. Marking: in research and test setups as precise reference points. Optical test setups: as a light source for beam splitting, diffraction and interference experiments. Workpiece positioning: in production as a reference point for drilling and placement operations. Construction: plumb points, height references, wall alignment (not our domain – we supply industrial quality, not DIY plumb lasers).

Why does a green point laser look brighter than a red one?

The human retina is most sensitive in the green spectral range around 555 nm – that is the peak of the eye's spectral sensitivity. Green laser light at 520 nm sits close to this peak, while red light at 650 nm sits at the edge of visual sensitivity. Specifically: a 5 mW green point laser looks visually about as bright as a 25–35 mW red point laser. Practical effect: at equal perceived brightness, green gives you a lower laser class – Class 2 instead of Class 3R for red. This simplifies safety measures significantly. Trade-off: green laser diodes are more expensive and more temperature-sensitive than red ones.

What is beam divergence and why does it matter?

Beam divergence describes how strongly a laser beam expands with distance. It is measured in milliradians (mrad). Example: a beam with 1 mrad divergence widens by 10 cm over 100 m distance. For point lasers low divergence is desirable – so the dot stays sharp over long distances. Typical values: 0.5–2 mrad after collimation. Influencing factors: emitter size of the laser diode, quality of the collimator optics, wavelength. For our OEM modules the divergence is typically specified in each module's datasheet or optimized at the factory.

What do the laser classes 3R and 3B mean?

Class 3R: increased risk on direct viewing of the beam, but the natural blink reflex usually still provides sufficient protection. Safety goggles are recommended but not strictly required in all cases. Maximum 5 mW in the visible range. Class 3B: direct radiation is hazardous to the eye, but diffuse reflections are usually harmless. Safety goggles are mandatory in the open beam area. Beam enclosure where possible, clear marking of laser areas, training of personnel. Maximum 500 mW. Both classes require a laser safety officer in commercial use.

When to choose a point, line or cross laser?

Point lasers (also called dot lasers) project a sharp spot of light – ideal for precise single-point marking, distance measurement, triangulation and alignment tasks over large distances. Benefit: all the optical power is concentrated at the point, giving very high visibility even at low power. Line lasers project a line – ideal for cutting lines, paths and boundaries. Cross lasers project a cross from two lines – ideal for centring and 2D alignment. Rule of thumb: point for „this spot here“, line for „along this axis“, cross for „centred exactly on this intersection“.

Spot Lasers and Laser Modules for Industry and OEMs

Unsure about optics or angles?

Dot lasers in red, green and blue: frequently asked questions