Written by Ing. Iddrisu Danlard —Lecturer, Department of Electrical and Electronics Engineering, Sunyani Technical University.
The term photonics was derived from the Greek word “fos (φως),” meaning light. A photon is the smallest unit of light, which is a type of electromagnetic radiation. Photonics refers to the physical science and applications that generate, detect, and manipulate light (photons) through emission, modulation, transmission, signal processing, switching, amplification, and sensing. According to www.light2015.org, a website dedicated to highlighting global initiatives by the United Nations to enhance awareness of photonics and light-based technologies, “The 21st century will depend as much on photonics as the 20th century depended on electronics.”
Historically, photonics as a term appeared in the later part of the 1960s to describe a field of study whose objective was to utilize light to perform functions mainly in the field of electronics, such as telecommunications, data processing, computation, and so on. The field of photonics received a significant boost following the invention of the laser in 1960. Consequently, other developments such as optical fibers for transmitting data circa 1965, the laser diode in the 1970s, and the erbiumdoped fiber amplifiers in the late 1980s came to revolutionize the infrastructure for telecommunications and the internet in the late 20th century.
“The 21st century will depend as much on photonics as the 20th century depended on electronics.”
What is Photonics Engineering?
Photonics engineering is a branch of engineering that deals with the application of light-based technologies to develop, test, inspect, maintain, and repair systems and machinery. The primary purpose of the photonics engineering field is to develop new and innovative products for all sectors of the global economy. During the years preceding the dot-com crash in 2001, the field was primarily concerned with optical telecommunications. However, photonics engineering covers a huge range of science and technology applications.
Applications of photonics engineering
Photonics engineering has a wide range of applications. All aspects of human experience are represented, from the most basic to the most advanced applications in consumer products, telecommunications and information technology, construction, automobile and industrial manufacturing, aviation, military operations, entertainment, metrology, medical and biomedical diagnostics, photonic computing, and several others.
Consumer equipment
Technological applications of photonics engineering can be found in bar-code scanners, CD/DVD/Blu-ray devices, televisions, remote control devices, microwave heaters, optical data recorders, laser printers, digital cameras, cinema projectors, and many other products. Advanced lighting in shops allows colors of meat, vegetables, and clothes to appear aesthetic. Photonics engineering applications in illumination for schools and offices improve concentration levels and efficiency.
Consumer electronic products (left and middle) and illumination at a mall (right). Image sources: https://www.kenresearch.com/ and https://www.archilovers.com/
Telecommunications and Information technology
Photonics engineering applications in telecommunications and information technology include optical multiplexers, optical demultiplexers, polarization filters, optical splitters, optical amplifiers, lasers, optical switches, optical transmitters, photodetectors, optical circulators, wavelength converters, data center and cloud storage facilities. Internet data travels through optical fibers made of glass to transfer information across the globe.
Construction industry
Laser leveling and laser range finding are examples of photonics engineering applications in the construction industry. These applications allow accurate, fast, and automatic leveling and range finding in structural health monitoring. Advanced lighting in buildings using novel light-emitting diode (LED) and organic light-emitting diode (OLED) technologies provide astounding outlooks making cities more attractive and environmentally friendly. Various ultraviolet and infrared scanners are used for detecting cracks in building structures. Optical devices for surveillance of mechanical disturbances in buildings due to vibrations and other stresses are applications of photonics engineering. Highly sensitive systems for detecting fires, smoke, and combustible gases in buildings, as well as thermo-vision techniques, which allow visualization and evaluation of buildings for safety and economics, are further applications of photonics engineering.
Automobile and Industrial Manufacturing
High-power photonic lasers are used in industrial manufacturing for welding, drilling, cutting, and surface modification. Photonic sensors and night-vision cameras allow drivers to see in the dark to prevent accidents. Photonic technologies perform key roles in smart displays and lighting automobiles. When an automobile is fixed and repainted following an accident, for example, the repair should match the rest of the automobile in both color and texture. Moreover, many technicians operate by sight while making minor changes to original color formulations so that a new finish matches an existing color on the rest of the vehicle. Photonics engineering provides various capabilities to compare color hues and textures that the human eyes cannot discern.
Laser welding (left), 3D printed automotive part (middle), and a 3D printed engine block (right). Image sources: https://www.waynetrail.com/ and https://www.sculpteo.com/
Aviation industry
Photonics engineering is vital in the aviation industry. From head-up displays (HUDs) to onboard optical networks, photonics engineering improves aircraft monitoring and maintenance in ways that copper-based electrical systems cannot. While many advances in commercial aircrafts occur in the plane that passengers cannot see, certain implementations occur within the passenger cabin, such as LED lighting and electrochromatic window dimming. Thermal imaging is a technique used for aircraft inspection and quantitative evaluation of metallic and composite materials to analyze variations in densities caused by porosity, entrapped voids, delaminations, or microcracks in aviation materials. Photonics engineering technologies include infrared and x-ray scanners at airports. Optical humidity sensors have numerous in the aviation industry. Helmet mounted display (HMD) and near-eye display (NED) optics improve safety and situational awareness by presenting critical flight instrument data in front of the pilot's line of sight. In poor and deteriorating weather settings with limited vision and other environmental obstacles, HUD display technology provides considerable safety-of-flight advantages.
Military and quasi security operations
Because light travels quickly and is non-invasive, it has several military and quasi-security applications. The military extensively relies on the optical spectrum to detect, map, and identify adversary intent at long distances. Photonic technologies give higher-quality sensing and communication data needed in security operations. Multispectral imaging is an example of a photonics-based military technology that can extract substantially more information about its surroundings than traditional sensors. Multispectral imaging can be used to locate bombs, disclose enemy movements, and determine the depth of underground shelters. In the military, photonicsbased spectrometers and holographic imagers are also employed. A spectrometer is a type of chemical sensor that can detect explosives in liquids and solids.
A holographic imager is a technology that generates three-dimensional renderings of urban and hilly landscapes. Photonics-based imaging capabilities help troops to address obscuration of eyesight and long-range identification. These photonic devices are lightweight and tiny, making them portable for soldiers in the field. Command and control, navigation, search and rescue, mine laying and detection are all examples of photonic sensor applications. Telescopes for space exploration, night-vision goggles, high-resolution image cameras for border monitoring, and chemical detection sensors are examples of laser defense. Photonics technologies are used to analyze paintings to see hidden paintings and drawings as well as previous versions and sketches, which can be used to detect fraud and forgery.
Entertainment industry
One of the most common uses of photonics technology is in entertainment. Televisions are progressively incorporating complex displays into their designs, concert venues have giant LED walls, and holographic gaming is becoming more widespread. The need for more realistic experiences has led to the development of technologies such as OLED and Quantum Dots, which consume less power and have wider color gamuts than their predecessors. Displays are an important enabling technology for the information era. Over the last two decades, liquid-crystal displays (LCDs) have displaced cathode-ray tubes as the main kind of display. Several features of LCD technology advanced considerably over this period, including resolution, quality, dependability, size, affordability, and capabilities. Small screens are utilized in cell phones and tablets. In contrast big displays are used in desktop computers, table-top displays, televisions, and wall-mounted displays.
Furthermore, there is always a push towards larger screens. The usage of organic lightemitting diodes (OLEDs) in screens is becoming more popular. The use of LED as the primary pixel component in an OLED display eliminates the requirement for external back-lighting equipment. Quantum Dots, nanoparticle-sized semiconductors that emit light at specific frequencies, will be used in the next generation of displays. Flexible screens are an intriguing technology that can have a significant influence in the future. Newspapers, magazines, and “pulldown” screens made of flexible materials will replace traditional screens and projectors. LED lights and panels are increasingly replacing incandescent light bulbs and projection screens in performance venues. Their adaptability, brightness, movement diversity, and durability all contribute to their extensive use in the entertainment business. Light is a crucial component of art and culture. Lighting can be used artistically with low-cost equipment that almost everyone uses. Light painting (painting with light) is a novel and inventive method of using light-based technology in artistic exhibitions.
Laser shows in entertainment. Image sources: https://www.liquidskylasershow.com/ and https://www.addtoevent.co.uk/
Metrology
Optical metrology is the science and technology of measuring light. Autocollimators, particularly laser-based autocollimators, allow for precise angle measurements. Optical profilometers are widely used in semiconductor chip production and optical fabrication quality control to measure surface topographies. Form metrology also employs a variety of additional equipment to measure contours and surface roughness. Optical time-domain reflectometers are used to check fiber-optic networks and detect damaged fiber splices and connectors. Free-space reflectometers, for example, are used to characterize thin-film optical devices. Photodiodes and thermal power meters can be used to measure optical power. Photonic devices are used to determine optical intensity and brightness. Integrating spheres are used for radiation that is released in various directions. Optical frequency metrology is concerned with high-precision optical frequency measurements. One can make ultraprecise optical clocks that outperform atomic clocks. The use of fiber-optic temperature and strain sensors enables distributed sensing. They are utilized for taking measurements in industrial processing facilities, bridges, tunnels, buildings, oil and gas pipelines, and electricity transmission lines, among other things. Photonics and spectroscopy are also employed in agriculture, where sensors and cameras allow for the examination of soil and crops to determine which regions require fertilizers. Precision agriculture is the process of analyzing how ripe fruits are. Photonics technology can be used with machine vision equipment to analyze and sort ripe fruits.
Medical and Biomedical applications
Photonic chemical sensors and biosensors provide rapid and in-situ monitoring technology. Some applications of these sensors include food quality surveillance, human blood testing and analysis, DNA hybridization assay, enzyme detection, real-time monitoring of antigen-antibody reactions, quantification of proteins in biological samples during immunoassays [60], determination of association and dissociation constants in biochemical reactions, detection of human immunoglobulin G (IgG). Other applications include detection of pathogens and toxins in environmental and alimentary substances, determination of triacylglycerides in atherosclerosis, analysis of microenvironmental cellular interactions, detection of biomarkers of cancers, determination of glucose concentration levels in diabetic patients, biological gas concentration measurements, monitoring of drug-protein interactions, and nuclear receptor-DNA interactions, drug screening and drug discovery, as well as detection of hormones, and steroids.
Photonic computing
Unlike an electron-based computer, an optical computer uses photons to perform computations. Key merits of optical computers include small size, less power consumption, low heat dissipation, higher speed and performance, and scalability for all networks.
Summary of photonics engineering applications. Image source: https://www.thesamadhan.com/
Photonics Engineering in the Future
The potential economic effects of photonic technologies over the next decade are significant, with several industry groups predicting growth rates of up to 25% and total markets worth hundreds of billions of dollars. Between 2005 and 2011, growth in the photonics industry was more than twice that of the global GDP. Photonics applications currently account for about 15.5% of the European economy producing over €58.5 billion in the European photonics market. The global photonics market is estimated to be worth over €854 billion by 2025. According to Global Market Insights, the global photonic biosensor market alone is expected to hit USD 42 billion by 2027. Furthermore, the information sector, including its services, is expanding quickly across the world. Its yearly revenue is expected to reach one trillion dollars with 5 million employees. Are you interested in a career in Photonics Engineering? Click here to Apply to our BTech. Photonics Engineering programme.
References
www.light2015.org
https://www.kenresearch.com/
https://www.archilovers.com/
https://www.waynetrail.com/
https://www.sculpteo.com/
https://www.liquidskylasershow.com/
https://www.addtoevent.co.uk/
https://www.thesamadhan.com/
Ribeiro, P. A., & Raposo, M. (Eds.). (2018). Optics, Photonics and Laser Technology. Springer International Publishing.
Responsive Photonic Nanostructures: Smart Nanoscale Optical Materials, Editor: Yadong Yin RSC Cambridge 2013 https://pubs.rsc.org/en/content/ebook/978-1-84973-653-4
Willner, A. (2019). Optical fiber telecommunications (Vol. 11). Academic Press.
Chang, Frank (17 August 2018). Datacenter Connectivity Technologies: Principles and Practice. River Publishers. ISBN 978-87-93609-22-8.
Devgan, P. S. (2018). Applications of Modern RF Photonics. Artech House.
Danlard, I., & Akowuah, E. K. (2020). Assaying with PCF-based SPR refractive index biosensors: From recent configurations to outstanding detection limits. Optical Fiber Technology, 54, 102083.
Gangopadhyay, T. K., Kumbhakar, P., & Mandal, M. K. (Eds.). (2019). Photonics and Fiber Optics: Foundations and Applications. CRC Press.
Hausken, T. (2021). Optica Market Update: What to expect for the optics and photonics market for 2022.