Hall 5 ERA OF OPTICS

 

Introduction to the Hall

Welcome to the Hall of the ERA OF OPTICS. This hall focuses on hands-on experiences with key optical technologies and traces the development of modern optics. Covering an exhibition area of 665 square meters, the hall adopts orange as its main color tone, symbolizing vitality and innovation. Here, you will find exhibits on light sources, optical materials and cold-processing techniques, optical information technology, imaging and display technologies, sensing and detection technologies, human interaction with light environments, and other optical innovations. Step inside and experience the ongoing journey of optical creativity and progress.

Artificial Light Sources

The emergence of artificial light sources marked a milestone in the dawn of modern science. With the continuous invention of new light sources, humanity’s diverse needs for illumination have been met in ever more sophisticated ways. In this exhibit, you can view various types of light sources displayed in the cases and explore the development path of artificial lighting.

Lighting Across Space

This exhibit is Lighting Across Space. In the center, the colorful sphere is a plasma globe, and the movable tube is a fluorescent lamp. When you press the button, the fluorescent lamp lights up—why is that? Inside the lamp tube are low-pressure argon gas and mercury vapor, and its inner wall is coated with a layer of phosphor. The plasma globe generates an electrostatic field that excites the argon and mercury atoms inside the lamp. These atoms release energy in the form of ultraviolet light, which strikes the phosphor coating, causing it to emit visible light. This is why the lamp glows. As you move the tube upward and away from the plasma globe, the effect gradually weakens, and the light slowly goes out.

Lasers

The laser has been hailed as one of the greatest inventions of the 20th century, with wide-ranging applications in medicine, industry, communications, and defense—from cutting metal to correcting nearsightedness. Here, five typical types of lasers are on display. You can use the touchscreen to explore more knowledge about lasers and their applications.

The Birth of Optical Lenses

This exhibit is The Birth of Optical Lenses. In daily life, eyeglass lenses, microscopes, and camera lenses are all made from optical lenses. Optical glass is the most common material used to manufacture these lenses. Through videos and real objects on display, you can learn about the complete process of making an optical lens.

Quantum Communication

This exhibit is Quantum Communication, a new type of communication that uses the principle of quantum entanglement to transmit information. It is regarded as the most secure form of communication. In general, quantum communication involves two transmission channels: One transmits the entangled particles. The other is a classical channel that uses electromagnetic waves to transmit data information.

The encryption process works like this: A pair of entangled particles is prepared in advance and sent separately to the transmitter and the receiver via a quantum satellite. When the particle at the transmitter is measured, if it collapses into a “spin-up” state, then the particle at the receiver will instantaneously collapse into a “spin-down” state. This correlation can be jointly verified through the classical channel. If the two particles remain entangled, data transmission proceeds normally. If an eavesdropper tries to intercept, the entangled state is destroyed, leaving the particles in unrelated states. This disruption is detected immediately, and the transmitter automatically cuts off the connection to stop data transfer.

In this exhibit, the principle of quantum encryption is demonstrated in a simple and intuitive way. Robot A represents the transmitter, and Robot B represents the receiver. Press the button to power on: Robot A and Robot B connect, simulating the establishment of a secure link. Adjust the polarization knobs to align them, symbolizing the creation of an entangled state, and then transmit data via the console. If you deliberately rotate a polarization knob to simulate eavesdropping, the entanglement collapses, and Robots A and B move incoherently, with data transmission cut off.

Laser Eavesdropping

This exhibit is Laser Eavesdropping. Laser eavesdropping is a technology that uses a laser beam to illuminate a target surface, such as a windowpane, and detects subtle vibrations in the reflected beam caused by sound waves. By analyzing these vibrations, conversations inside the room can be reconstructed. This method allows long-distance eavesdropping from several hundred meters away, without any physical contact with the target object, and it is difficult to detect with conventional anti-bugging equipment.

Here, you can try the demonstration: Point the laser toward the window of the room in the center, adjust the control handle to find the best position, and then listen through the headphones—you will hear the voices from inside the room.

Optical Information Storage

This exhibit is Optical Disc Storage. CDs and VCDs are familiar examples of optical discs used as carriers for information storage. Optical discs feature high storage density, strong resistance to electromagnetic interference, long lifespan, non-contact read/write capability, and low cost. You can rotate the display disc and, through the overhead monitor, learn about the different types of optical discs, their capacities, and their characteristics.

Optical Fiber Communication

This exhibit is Optical Fiber Communication. Optical fiber communication uses light waves as information carriers and optical fibers as the transmission medium. It has many advantages: large capacity, long transmission distance, high confidentiality, excellent transmission quality, and relatively low cost. However, fiber optic lines must be physically installed, which limits their flexibility. They are mainly used in networks, medical systems, and image transmission. On your right, you can see an enlarged model of an optical fiber. Observe the light path carefully—does it match what you imagined?

Space Laser Communication

Laser communication refers to the transmission of information between two terminals using a laser beam as the carrier. The information is encoded onto the laser, transmitted through space, and then collected at the receiving end by a photodetector, where it is converted back into electrical signals and restored into the original information—thus enabling two-way communication.

Space laser communication has remarkable advantages: large capacity, high speed, wide bandwidth, strong resistance to electromagnetic interference and interception, compact and lightweight design, and excellent confidentiality. Compared with wired and fiber-optic communication, it is more flexible, less disruptive to urban infrastructure, and easier to deploy. It does not occupy radio spectrum resources, requires no frequency license, avoids pipeline construction or road excavation, and can be set up with great flexibility. It enables tasks that optical fiber communication cannot achieve, such as ground-to-ground, ground-to-air, and air-to-air links. Today, space laser communication is widely used in satellite-to-Earth communication, military communication, and broadband networks.

The interactive system in front of you demonstrates this process. A camera captures video signals, which are converted into laser signals by an electronic system and transmitted through space to a light receiver. The receiver collects the light signal, restores it into the original video, and displays it on the screen.

You can try blocking the laser path with your hand or a piece of cardboard. What happens? When the laser beam is interrupted, the video on the screen disappears—this proves that the video signal is being transmitted via laser, and blocking the beam disrupts the communication.

Adaptive Projection

This exhibit is Adaptive Projection. Adaptive projection technology can automatically adjust to the shape and position of the projection surface, ensuring that the image is accurately projected onto moving objects. You are invited to try it out: freely move the object on the platform, press the button, and observe how the image follows and is projected onto the object’s surface in real time.

Optical Anti-Counterfeiting Technology and Its Applications

This exhibit is Optical Anti-Counterfeiting Technology. Optical anti-counterfeiting is developed based on the principles of reflection, refraction, and holography, and has been widely applied in banknotes, bank cards, identity cards, and many other areas. Here you can observe real samples to gain a straightforward understanding of how optical anti-counterfeiting is used in daily life.

Microlens Arrays

A microlens array consists of many tiny sub-lenses, with diameters ranging from a few hundred nanometers to several millimeters, arranged systematically on a substrate. Microlens arrays are widely used in advanced optical imaging, 3D displays, and semiconductor lighting, with applications such as beam shaping, wavefront sensing, and moiré imaging.

Press the power button on the left to activate the laser, then rotate the microlens array disc and observe how the laser spot on the background panel changes shape. You will see circular, square, and triangular light spots—the microlens array alters the beam’s profile, demonstrating its role in beam shaping.

Next, rotate the microlens array disc on the right and watch the projection. When the disc turns to a specific position, the letters “OK” will appear—this is an application of moiré imaging.

Evolution of Displays

This wall showcases the Evolution of Displays. With the progress of electronics and optics, displays have undergone multiple generations of transformation, with steadily improved image quality and clarity while reducing energy consumption. The evolution has progressed from cathode ray tube (CRT) displays, to plasma display panels (PDP), to liquid crystal displays (LCD), and then to organic light-emitting diode (OLED) displays and laser TVs. In addition, we have connected a 4K camera to a 4K display. You can watch the high-definition footage captured by the camera in real time, experiencing the latest achievements in display technology.

Naked-Eye 3D

This exhibit demonstrates naked-eye 3D technology, which comes in two main forms: parallax barrier technology and lenticular lens technology. The naked-eye 3D display here uses the lenticular lens method. Its principle is to place a lenticular lens layer in front of the LCD screen, aligning the image plane with the lens’s focal plane. The pixels on the screen are divided into sub-pixels projected in different directions. When each eye views the screen from a slightly different angle, the eyes perceive different sub-pixels. The result is a 3D effect without the need for special glasses, allowing us to enjoy immersive 3D experiences right at home.

High-Speed Photography

This exhibit is High-Speed Photography, also known as a time magnifier. By slowing down fast-moving images to a speed perceivable by the human eye, it makes fleeting phenomena visible. High-speed photography is widely used in sports broadcasting, scientific research, and other fields. Beside you is a high-speed photography booth, recreating a real shooting setup for high-speed video.

Hyperspectral Imaging

This exhibit is Hyperspectral Imaging. Hyperspectral imaging captures images of objects within very narrow wavelength ranges, revealing unique features at different spectral bands. It plays an important role in remote sensing, authentication, anti-counterfeiting, and related applications.

Directly viewing the screen ahead makes it difficult to distinguish details. Please look through the observation window while rotating the filter wheel to switch between filters of different colors. Do you notice any changes? With each filter, the image becomes clearer, and a different view appears. The system uses four filters within the visible spectrum, each corresponding to a specific wavelength. A filter only allows light of its own color to pass through, making spectral differences directly visible to the naked eye.

Principle of High-Speed Photography

This exhibit explains the Principle of High-Speed Photography. To begin, press the start button to activate the camera. Then, strike quickly toward the device in the center. The high-speed camera will capture that instant, and the slow-motion footage will immediately play on the display. Normally, a punch is too fast for the human eye to follow, as human temporal resolution is limited to about 1/24 of a second. However, high-speed cameras, capable of recording 1,000 to 10,000 frames per second, capture such fleeting actions with clarity, then replay them at normal speed for detailed observation.

Today, high-speed photography is widely applied in industry, scientific research, and defense. For example, it is installed on assembly lines to replace manual inspections. It also enables scientists to observe microscopic reactions such as lattice vibrations or explosion tests—phenomena far too rapid for the naked eye to perceive.

Growing Toward the Light

This exhibit is Growing Toward the Light. Press the button to power on the system, then pick up the LED light source and shine it on the sunflower model from different directions. You will notice the sunflower turning to follow the light. When the light source is removed or switched off, the sunflower stops moving. This device uses a dual-axis automatic tracking system, consisting of photosensitive elements, a signal-processing circuit, and an angle-adjustment mechanism. A photoresistor is mounted on the sunflower. As the light source moves, the photoresistor generates an electrical signal, which is processed by a microcontroller to drive the motor, causing the sunflower to turn and continuously follow the light.

Capturing the Superhero

This exhibit is Capturing the Superhero, simulating Spider-Man playfully dodging the camera. There are four buttons on the tabletop. Pressing any button causes Spider-Man to fall in the opposite direction, as if avoiding the light. Why does this happen? When a button is pressed, the light source switches on and triggers the camera to take a photo of Spider-Man. At the same time, the light beam reaches the photosensor on the base of the Spider-Man figure, which activates its internal mechanical structure and makes the figure topple in the opposite direction. This is a fun demonstration of a simple application of the photoelectric effect.

3D Scanning and Imaging

This exhibit demonstrates 3D Scanning, 3D Printing, and Laser Engraving Technology. The 3D scanner uses binocular vision or structured light projection to capture data of an object, which is then processed to generate a three-dimensional image. The 3D printer can reproduce a physical replica identical to the scanned object, while the laser engraving machine can carve a three-dimensional image inside glass, producing a vivid internal hologram.

Secrets of the Digital Camera

Welcome to Secrets of the Digital Camera. At the entrance, you will see an enlarged model of a digital single-lens reflex (DSLR) camera. A camera mainly consists of a lens, reflex mirror, pentaprism, shutter, and image sensor. Unlike film cameras that record images on photographic film, digital cameras use image sensors such as CCD or CMOS to digitally capture and record images. Digital photos can be instantly replayed and easily processed afterward. Through the graphic panels and multimedia displays, you can further explore how a digital camera works. Inside the display case, you will find a disassembled miniature DSLR camera, showcasing the internal structure and imaging principle of mirrorless digital cameras.

Transparent LCD Wall

Welcome to the Transparent LCD Wall. This installation utilizes the optical properties of liquid crystal materials. A photoelectric sensor detects human motion and controls the liquid crystal layer, which acts like a gate—either blocking light or allowing it to pass through. A designated area is marked on the floor in front of the exhibit. Stand in this area, wave your arms, and interact directly with the Transparent LCD Wall.

Photoelectric Encoder

Here you will see actual specimens of photoelectric encoders. Photoelectric encoders measure displacement and angular position through photoelectric conversion and are widely used in modern servo systems. Detailed explanations are provided on the adjacent graphic panels.

Fiber-Optic Sensors

This section presents several fiber-optic sensors. Fiber-optic sensors are valued for their high sensitivity, high resolution, compact size, strong resistance to electromagnetic interference, and high reliability. You can learn more about their principles and applications through the graphic panels on display.

Photoelectric Detectors

Displayed here are photoelectric detectors, devices that convert optical radiation into electrical signals. They are generally classified into two types: thermal detectors and photon detectors. The CCD and CMOS sensors widely used in digital cameras are two common examples of photoelectric detectors. You can learn more about other types of detectors from the graphic panels.

Photoelectric Sorting

This exhibit demonstrates photoelectric sorting. An image sensor detects the color and shape of small balls. Based on the results, a motor directs each ball into a designated slot, then proceeds to the next ball until the sorting process is complete. Press the Start button on the screen, choose a sorting mode, and observe the sorting process in action. Photoelectric sorting offers advantages such as non-contact measurement, continuous operation, high speed, and precision, helping industries improve processing efficiency, enhance product quality, and reduce costs. Today, it is widely applied in food processing, mining, agriculture, and other fields.

Humans and Light Environment

You are now entering the Humans and Light Environment section. The color of the surrounding environment can influence human physiological states. Here you can observe how color, angle, and illuminated area of light affect human perception and well-being.

Color and Grayscale

This exhibit explores the relationship between color and grayscale. Press the button to light up the grayscale panel, then rotate the dial. For example, through the red viewing window, observe how the perceived color changes.

Grayscale is one of the three attributes of color, alongside hue and saturation. Any color we perceive is the result of these three properties combined. Grayscale itself has no color—it represents a gradation between black and white. Grayscale corresponds to brightness: the lower the percentage, the higher the brightness; the higher the percentage, the darker the image appears.

 

This concludes your journey through the Hall of the Age of Light. Please proceed to the hall of APPLICATIONS OF OPTICS.