What are Multi-emitter laser diodes?
Multi-emitter laser diode (Bar package)
Multi-emitter (multiple ridges) laser diode
A multi-emitter laser diode is a type of laser diode that has a multi-emitter (multiple ridges) to emits the laser beam. It operates at an output wavelength ranging from 630 to 1650 nm and delivers an output power of 0.5 to 510 W. The emitter width usually varies from 95 to 350 µm. These types of diodes can deliver laser lights with high output power. They are ideal for use in solid-state laser pumping, medical, and material processing applications.
The multi-emitter laser diodes are available in the following packages.
1. Free space multi-emitter laser diodes
2. Fiber-coupled multi-emitter laser diodes
The free space multi-emitter laser diode delivers the laser beam in free space. In a fiber-coupled multi-emitter laser diode, the laser beam propagates through a fiber optic cable by following the principle of total internal reflection. The fiber-coupled laser diodes transfer the data or signal to the required place as well as connect the multi-emitter laser diodes to the other optic components.
Key Specifications of multi emitter laser diodes:
Central wavelength: Represents the wavelength of laser beam emitted from the multi emitter laser diode. The wavelength is represented in nm (nanometre).The multi emitter laser diodes can have a wavelength range of 630nm to 1650nm.
Configuration: Multi emitter
Output power: Represents the output power of the multi emitter laser diode. Usually, the multi emitter laser diodes can have the output power range of 0.5W to 510 W.
Spectral width: It is the width of the optical spectrum at the half-maximum power. It is represented in nm. Usually, the spectral width of multi emitter laser diodes can vary from 3nm to 20nm.
Type: Free space/ Fiber coupled
Threshold current (Ith): It is the current at which the output optical power increases sharply. When the laser diode is biased below this threshold current, the output optical power will be very low. It is represented in xA. The threshold current is proportional to the output power. Generally, the multi emitter laser diodes can have the threshold current range of 0.5A to 12 A.
Emitter width: Represents the width of the light emitting area. The range of emitter width can vary from 95µm to 350µm.
Number of emitter: Represents the number of emitter available with the multi emitter laser diode.
Vertical Divergence Angle (θ⊥): The angle at which the light-emitting band spreads in a direction vertical to the PN junction. It is usually in the range of 15˚-40˚.
Horizontal Divergence Angle (θ∥): The angle at which the light-emitting band spreads in a direction parallel to the PN junction. Typically, it is in the range of 6˚-10˚.
Operating current: It is the driving current or input currents when the multi emitter laser diode reaches the rated power. It is represented in xA. The operating current is proportional to the output power. For example, the operating current of a multi emitter laser diode may be 65 A for 173 W power output.
Operating voltage: Represents the supply voltage.
Operating temperature: Represents the safe operating temperature of the multi emitter laser diode. Typically, it has a range of 10 °C to +35°C.
Storage temperature: Represents the storage temperature range of multi emitter laser diode. Typically, it has a range of -20 °C to +80°C.
Package type: Represents the type package used to assemble the multi emitter laser diode. The multi emitter laser diodes are available in surface mount, module, bar, HHL, and TO-can.
