518 nm 30 mW OSRAM PLT5 516FB green laser diode

Q: Which well-known manufacturers of laser diodes exist?

The leading manufacturers of industrial laser diodes: Nichia (Japan) – market leader for green and blue laser diodes, highest efficiency and service life; well-known models include the NDG7575 (1 W green, 520 nm) and the NUBM series (blue). Sharp (Japan) – strong second source for visible wavelengths; models such as GH05C01B9G (1 W green). Osram Opto Semiconductors (Germany) – broad portfolio from 405 to 850 nm. Sony – mainly for display and show applications. Ushio – industrial high-power diodes. For red and infrared the choice is wider; for green and blue Nichia and Sharp are the dominant sources.

Q: How does beam shaping (collimation) of a laser diode work?

A bare laser diode emits a strongly divergent, elliptical beam – the bare diode does not produce a usable spot but rather a fanned-out cone. For practical use the beam must be collimated – reshaped into a parallel, directed beam. Standard solution: a collimator lens directly in front of the diode, mounted in an M9 × 0.5 housing (brass or aluminium). A single-lens optic turns the divergent beam into an approximately parallel beam. On high-quality collimators (e.g. our Colli-LA) we use an aspheric glass lens with AR coating, 5 mm aperture, focal length approx. 4 mm. For especially round beam profiles, correction optics can be added behind the collimator.

Q: Why does a laser diode need a heat sink?

Laser diodes dissipate typically 50–70 % of the electrical power as heat – only a fraction becomes light. A 1 W laser diode therefore generates 1.5–2 W of waste heat in the semiconductor chip. Without a heat sink the junction temperature climbs to critical levels within seconds and the diode fails thermally. Consequences: drastic wavelength shift (red-shifted), efficiency collapse, irreversible destruction. Rule of thumb: every additional 10 °C in junction temperature roughly halves the service life. Practice: mount the diode in a massive metal holder (brass or aluminium), the holder on a heat sink with thermal compound, and add a fan or thermal convection for &gt; 1 W.

Q: What is a constant-current driver for laser diodes?

A constant-current driver is an electronic circuit that regulates the current flowing through a laser diode to an exact value – independent of input voltage and temperature variations. This is necessary because a laser diode's optical output depends linearly on current, not on voltage. A simple voltage supply would, with small temperature or supply fluctuations, lead to large current and therefore optical-output swings – in the worst case destroying the diode. Good drivers offer: constant-current regulation, soft-start, over-temperature protection, ESD protection and often analog/TTL modulation for pulsed operation. Matching drivers are available in our „Laser drivers“ category.

Q: How is a bare laser diode driven correctly?

A bare laser diode needs a constant-current driver – not a simple voltage supply. Reason: the diode has a very steep current/light-output curve. Even 5 % current variation can destroy the diode. Concrete requirements: 1. Constant-current-regulated supply at the operating current specified in the datasheet (e.g. 1.6 A for Nichia NDG7575). 2. Soft-start (no abrupt current jump). 3. Protection against voltage spikes on the supply side. 4. Adequate heat dissipation via a heat sink (typically &lt; 30 °C junction temperature). 5. ESD protection during handling – bare diodes are extremely ESD-sensitive.

Q: What is a TO-9 laser diode?

TO-9 is a standardized package format for laser diodes – a cylindrical metal can with 9 mm diameter. The package contains the laser semiconductor chip, a protective cap with exit window and the electrical pins (typically 3). Benefits: uniform mechanical interface, good heat dissipation through the metal housing, easy integration into sockets and heat sinks. TO-9 is, alongside TO-5 (5.6 mm) and TO-18 (5.6 mm, older), the most common package for high-power laser diodes with &gt; 200 mW. Examples: Nichia NDG7575 (1 W green), Sharp GH05C01B9G (1 W green). A bare TO-9 diode is a pure component without collimator and without driver.

PLT5 516FB: green OSRAM laser diode, 30 mW (518 nm), in a 5.6-mm package, operating current only about 80 mA.

€9.52

Product number: PLT5 516FB

518 nm 30 mW OSRAM PLT5 516FB green laser diode

PLT5 516FB – OSRAM Green Laser Diode, 30 mW (518 nm): Green laser diode from OSRAM in a 5.6-mm package with 30 mW output (at 25 °C package temperature) and an operating current of only approx. 80 mA—energy-efficient and compact for modules and measurement setups.

Green laser diode, 518 nm (±5 nm), 30 mW
Low operating current: approx. 80 mA
Compact 5.6-mm package

Technical Specifications

Output power:	30 mW @ Tcase 25°C
Operating current:	80 mA
Maximum operating current:	100 mA
Operating temperature:	-20 to +60° C
Wavelength:	518 nm, ±5 nm
Polarization ratio:	20:1

Which well-known manufacturers of laser diodes exist?

The leading manufacturers of industrial laser diodes: Nichia (Japan) – market leader for green and blue laser diodes, highest efficiency and service life; well-known models include the NDG7575 (1 W green, 520 nm) and the NUBM series (blue). Sharp (Japan) – strong second source for visible wavelengths; models such as GH05C01B9G (1 W green). Osram Opto Semiconductors (Germany) – broad portfolio from 405 to 850 nm. Sony – mainly for display and show applications. Ushio – industrial high-power diodes. For red and infrared the choice is wider; for green and blue Nichia and Sharp are the dominant sources.

How does beam shaping (collimation) of a laser diode work?

A bare laser diode emits a strongly divergent, elliptical beam – the bare diode does not produce a usable spot but rather a fanned-out cone. For practical use the beam must be collimated – reshaped into a parallel, directed beam. Standard solution: a collimator lens directly in front of the diode, mounted in an M9 × 0.5 housing (brass or aluminium). A single-lens optic turns the divergent beam into an approximately parallel beam. On high-quality collimators (e.g. our Colli-LA) we use an aspheric glass lens with AR coating, 5 mm aperture, focal length approx. 4 mm. For especially round beam profiles, correction optics can be added behind the collimator.

Why does a laser diode need a heat sink?

Laser diodes dissipate typically 50–70 % of the electrical power as heat – only a fraction becomes light. A 1 W laser diode therefore generates 1.5–2 W of waste heat in the semiconductor chip. Without a heat sink the junction temperature climbs to critical levels within seconds and the diode fails thermally. Consequences: drastic wavelength shift (red-shifted), efficiency collapse, irreversible destruction. Rule of thumb: every additional 10 °C in junction temperature roughly halves the service life. Practice: mount the diode in a massive metal holder (brass or aluminium), the holder on a heat sink with thermal compound, and add a fan or thermal convection for > 1 W.

What is a constant-current driver for laser diodes?

A constant-current driver is an electronic circuit that regulates the current flowing through a laser diode to an exact value – independent of input voltage and temperature variations. This is necessary because a laser diode's optical output depends linearly on current, not on voltage. A simple voltage supply would, with small temperature or supply fluctuations, lead to large current and therefore optical-output swings – in the worst case destroying the diode. Good drivers offer: constant-current regulation, soft-start, over-temperature protection, ESD protection and often analog/TTL modulation for pulsed operation. Matching drivers are available in our „Laser drivers“ category.

How is a bare laser diode driven correctly?

A bare laser diode needs a constant-current driver – not a simple voltage supply. Reason: the diode has a very steep current/light-output curve. Even 5 % current variation can destroy the diode. Concrete requirements: 1. Constant-current-regulated supply at the operating current specified in the datasheet (e.g. 1.6 A for Nichia NDG7575). 2. Soft-start (no abrupt current jump). 3. Protection against voltage spikes on the supply side. 4. Adequate heat dissipation via a heat sink (typically < 30 °C junction temperature). 5. ESD protection during handling – bare diodes are extremely ESD-sensitive.

What is a TO-9 laser diode?

TO-9 is a standardized package format for laser diodes – a cylindrical metal can with 9 mm diameter. The package contains the laser semiconductor chip, a protective cap with exit window and the electrical pins (typically 3). Benefits: uniform mechanical interface, good heat dissipation through the metal housing, easy integration into sockets and heat sinks. TO-9 is, alongside TO-5 (5.6 mm) and TO-18 (5.6 mm, older), the most common package for high-power laser diodes with > 200 mW. Examples: Nichia NDG7575 (1 W green), Sharp GH05C01B9G (1 W green). A bare TO-9 diode is a pure component without collimator and without driver.