The retro trend has swept the digital world, and these smash hit products have a "successor"

CCD cameras, CDs, 3DS game handhelds...

These scorching digital products have a "successor"

◎ Intern reporter Du Qian

When the words antique and digital are put together, what can you think of?

Today, with the rapid iteration of digital technology and the emergence of new products, there are still people who love digital products that have long been eliminated by the times.

In recent years, a retro trend has swept the digital world, with CCD cameras, CD discs, vintage game consoles... Similar "digital antiques" appear frequently on some social platforms.

In addition to getting novel experiences and reliving the beauty of that era, we can also feel the progress of science and technology from these digital products that have long been withdrawn from the stage of the times.

CCD cameras were replaced by CMOS-based devices

CCDs stand for Charge-Coupled Devices. For a long time since the invention of digital cameras, CCDs have been the only choice for image sensors for digital cameras.

"The function of the image sensor is mainly to convert optical image signals into electrical signals, which act like the retina of the human eye." Yan Huaizhi, director of the Institute of Network and Security of Beijing Institute of Technology, said in an interview with Science and Technology Daily that CCDs can achieve photoelectric conversion and use photodiodes. It has been used for half a century and was once a leader in the field of image sensors.

At that time, CCD cameras were the mainstream of digital cameras. However, the good times did not last long, and cameras using CMOS (complementary metal oxide semiconductor) image sensors emerged after entering the 21st century, and soon replaced the dominance of CCD cameras in digital cameras.

Yan Huaizhi said that compared with CCD, CMOS image sensor in the photoelectric conversion process, that is, when the optical image signal is converted into an electrical signal, the relevant charge can be directly converted into voltage and reading, the conversion process is more direct, simple and efficient, so the latter has significant advantages in production cost, response speed and power consumption. Finally, after continuous technical iteration, CMOS has become the best choice for image sensors in many cameras, mobile phones, drones and other products.

Innovation did not stop there, and CMOS image sensors were "played" with new tricks. For example, in order to maximize the single pixel area of CMOS in the limited space of smartphones, many mobile phone manufacturers today use multi-pixel compositing technology. Its technical principle is that when taking photos, multiple pixels can be merged into one pixel for photosensitivity, so that the area of a single pixel is increased without changing the size of the image sensor, effectively improving the photosensitivity of a single pixel, enhancing the shooting quality in dark light, and improving the purity of the photo. However, such "magic" also comes at a price. When multiple pixels are combined into a single pixel, the number of pixels in the output photo is significantly reduced. For example, an image sensor with 4800 million pixels can reduce the number of pixels in its output photo to 1200 million when "four-in-one" multi-pixel compositing is applied.

In addition to working image sensors, the field of photography has ushered in a truly intelligent revolution in recent years. Some camera manufacturers use neural networks, deep learning and other technologies to allow artificial intelligence to "learn" a large amount of image data, so that it can help the camera greatly improve the image quality when shooting, and have better performance in noise reduction, color and lens defect correction. Even before the shutter is pressed, artificial intelligence is deeply involved in the shooting process. For example, a camera manufacturer has greatly improved the ability of the camera's focusing system with the help of artificial intelligence chips. When a person appears in the frame, the camera can instantly identify the subject of the person in the picture and lock the focus on the person. In addition, artificial intelligence can also help the camera further expand the categories of subjects that can be recognized, and can accurately identify and capture seven kinds of subject objects, including vehicles and insects.

The online streaming music platform "baton" CD

In addition to the recent fire of CCD cameras, CD discs and CD players, which have gradually disappeared in the music market, have also reappeared in the public eye.

CD player was born in the 80s of last century and has a history of more than 40 years. The advent of CD discs and CD players marked the transition from analog to digital recording of music.

The basic principle of recording music on CD discs is to create uneven trajectories on the surface of the disc by burning to represent 0 and 1, thereby converting sound signals into digital signals for storage. When the CD player reads the CD, the laser pickup and other components are used to emit the laser to the surface of the disc, because the surface of the disc is burned with many pits, so when the beam hits the pit, the reflected light is weak, and the signal picked up by the photodetector is small; When the beam hits the surface without pits, the reflected light is strong, and the picked up signal is large, so as to realize the reading of 0 and 1 digital signals.

However, after the popularization of MP3 and smart phones, the carrier of mainstream people listening to music has changed, and online streaming music platforms have "taken over" CDs and become the main way to record music.

Listeners no longer need to buy physical discs or download music files on their computers, open the online music app on their mobile phones, and the notes will "flow" from them, truly enabling music to surround them anytime, anywhere.

However, in order to meet the online needs of tens of millions of users, online music apps need strong technological support. Yan Huaizhi said that today's people can enjoy music conveniently and smoothly, mainly thanks to the rapid development of mobile communication technologies such as 5G and near-field communication technologies such as Wi-Fi and Bluetooth, and behind this is the huge improvement of the entire network service supply capacity including computing power, algorithms, storage, etc.

Thanks to the development of technology such as Bluetooth, people can also get rid of the shackles of the device cable when listening to music.

"For the general public, the wireless transmission and playback of music represented by Bluetooth technology can already replace wired transmission, whether in transmission, decoding speed or quality." Yan Huaizhi added that in order to solve the problem that Bluetooth wireless transmission methods are susceptible to interference from electromagnetic spectrum, signal quality, network environment and other factors, Bluetooth anti-interference and other technologies have been continuously improved in recent years, and the sound quality of Bluetooth music has become increasingly perfect.

In addition, near-field communication (NFC) technology has gradually become popular in headphones, speakers and other devices over the years, and users only need to touch the NFC-enabled mobile phone with it, which can save the cumbersome pairing process and achieve rapid pairing between the two.

VR replaces naked-eye 3D as the development direction of game console technology

"Digital antiques" are not all outdated items, but there are also products that were "ahead" of their time and are still amazing today. Today, when advanced display technologies such as virtual reality (VR) and ray tracing are widely used in video games, some gamers have revived a game handheld that was popular 10 years ago - the 3DS produced by Nintendo of Japan.

At the time, the biggest selling point of the 3DS was its glasses-free 3D effect. The handheld uses light barrier 3D technology to block part of the light source by adding a polarizing film to the LCD display, so that the left and right eyes input different images, "tricking" the brain, forming a naked-eye 3D effect. In addition to this, players can also take 3D photos and videos through the two cameras that come with the 3DS. However, the light barrier 3D technology is very demanding on the viewing angle, the line of sight must be perpendicular to the screen to achieve the best 3D effect, once the line of sight is shifted, the picture will appear ghosted.

Perhaps because the idea of implementing glasses-free 3D in handheld game consoles was too advanced, the software and hardware technology at that time was not enough to perfectly support this idea, and there were very few games that could really fit the naked-eye 3D effect, and the display effect was always unsatisfactory. Eventually, the 3DS's glasses-free 3D capabilities faded out after several product iterations.

However, the idea of glasses-free 3D games is still a bit ahead of its time today. Today, with the help of advanced equipment equipped with VR and other technologies, the immersive effect of games has been developed like never before. VR technology provides players with an unparalleled gaming experience by recognizing the surrounding environment and tracking people's eyes, gestures, gestures, etc. In addition, augmented reality (AR) technology has also developed rapidly in recent years, and there has been a trend of convergence between VR and AR, and the integration of the two will expand the application scope of VR technology. (Science and Technology Daily)