Courtesy from Significant Technologies Sdn Bhd LIGHT SOURCE & POWER METER/ PASSIVE DEVICES

Courtesy from Significant Technologies Sdn Bhd PASSIVE VS ACTIVE Active – need external power (ELECTRICITY) to perform Passive – no external power required

Courtesy from Significant Technologies Sdn Bhd Part I: Optical Passive Devices

Courtesy from Significant Technologies Sdn Bhd Optical Couplers Couplers can perform both combining and splitting. The devices are widely used in optical LAN and broadcasting networks

Courtesy from Significant Technologies Sdn Bhd Optical Couplers An optical coupler is a passive (unpowered) device that diverges (1:N) or converges (N:1) optical signals from one fibre or optical signal path to more than one (or vice versa.) Configurations: Splitters, taps, combiners, directional couplers

Courtesy from Significant Technologies Sdn Bhd Optical Couplers: Fabrication techniques Fusion – Most popular type of coupler – Fiber based _ Can not be mass-produced Mechanical – Earlier technique – Optics based – Fussy Mask and etch – Growing in popularity – Future technology - Waveguide based

Courtesy from Significant Technologies Sdn Bhd Optical Couplers: Characteristics COUPLING RATIO

Courtesy from Significant Technologies Sdn Bhd Optical Couplers EXCESS LOSS –Ratio of the input power to the total output power

Courtesy from Significant Technologies Sdn Bhd Optical Couplers INSERTION LOSS

Courtesy from Significant Technologies Sdn Bhd Optical Couplers DIRECTIVITY

Courtesy from Significant Technologies Sdn Bhd Couplers - Fabrication

Courtesy from Significant Technologies Sdn Bhd P0P0 P3P3 P2P2 P1P1 A B ISOLATORS

Courtesy from Significant Technologies Sdn Bhd ISOLATOR SPECIFICATION

Courtesy from Significant Technologies Sdn Bhd Couplers and Isolator in Optical Amplifiers

Courtesy from Significant Technologies Sdn Bhd CIRCULATORS Optical circulators redirects light sequentially from port-to-port in a unidirectional path Same characteristics as isolators by looking port port 2-3

Courtesy from Significant Technologies Sdn Bhd Applications: Optical Amplifier Add-Drop Multiplexer Bi-directional transmission To monitor back-reflection from devices or optical subsystems Characteristics: high isolation low insertion loss can have more than 3 ports CIRCULATORS

Courtesy from Significant Technologies Sdn Bhd CIRCULATORS: APPLICATION

Courtesy from Significant Technologies Sdn Bhd Fiber Bragg Gratings A grating is a periodic structure or perturbation in a material that creates a property of reflecting or transmitting light in a certain direction depending on the wavelength. External writing technique using UV light

Courtesy from Significant Technologies Sdn Bhd Reflection Transmission Fiber Bragg Gratings

Courtesy from Significant Technologies Sdn Bhd Characteristics: high reflectivity to be used as a filter low insertion loss low cost/simple packaging Fiber Bragg Gratings

Courtesy from Significant Technologies Sdn Bhd Transmission spectrum band-rejection filter Fiber Bragg Gratings

Courtesy from Significant Technologies Sdn Bhd Reflection spectrum reflective filter Fiber Bragg Gratings

Courtesy from Significant Technologies Sdn Bhd FBG APPLICATIONS

Courtesy from Significant Technologies Sdn Bhd Laser diode wavelength stabilizer FBG APPLICATIONS

Courtesy from Significant Technologies Sdn Bhd FIBER BRAGG GRATING SPECS.

Courtesy from Significant Technologies Sdn Bhd ATTENUATORS Function: To decrease light intensity (power) Working Principles Fiber displacement Rotating an absorption disk

Courtesy from Significant Technologies Sdn Bhd Characteristics: low insertion loss dynamic attenuation range wide range of operating wavelength high return loss Applications: adjust optical power to the dynamic range of receivers equalize power between different WDM signals To avoid receiver saturation ATTENUATORS

Courtesy from Significant Technologies Sdn Bhd Mechanical attenuator - by adjusting a screw Waveguide attenuator - by adjusting biasing current ATTENUATORS

Courtesy from Significant Technologies Sdn Bhd 20 dB Pin = 0 dBm Insertion loss = 2 dB Pout = = -22 dBm Programmable attenuator ATTENUATORS

Courtesy from Significant Technologies Sdn Bhd Part II. Optical Active Devices

Courtesy from Significant Technologies Sdn Bhd TX - RX

Courtesy from Significant Technologies Sdn Bhd Light Sources 2 types – Semiconductor Lasers Fabry Perot Laser Diode (FP) Light Emitting Diode (LED) Distributed Feedback Laser Diode (DFB) VCsel laser – Fibre Lasers Ring Lasers

Courtesy from Significant Technologies Sdn Bhd Light Emitting Diode

Courtesy from Significant Technologies Sdn Bhd Fabry Perot Laser Diode

Courtesy from Significant Technologies Sdn Bhd Distributed Feedback Laser Diode