What Is the Difference Between Virtual Reality and Augmented Reality?

Augmented Reality (Augmented Reality) technology is a technology that intelligently fuses virtual information with the real world. It uses a variety of technical methods such as multimedia, 3D modeling, real-time tracking and registration, intelligent interaction, and sensing. After the virtual information such as text, image, three-dimensional model, music, and video are simulated and applied to the real world, the two kinds of information complement each other, thereby achieving "enhancement" of the real world. ^[1]

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2018-05-29 11:05 Three mountains that AR cannot currently cross: field of view, understanding of objects, and adaptive design

After Apple and Google joined the AR battle, the hotness of the technology was instantly elevated to a level. In front of tens of millions of potential users, the developers also mobilized and prepared to provide the market with an attractive and immersive AR experience. The magical magic we've seen on video seems to be coming true. ... more

Augmented reality overview

Augmented Reality (AR). Augmented reality technology is also called augmented reality. AR augmented reality technology is a newer technology content that promotes the integration between real-world information and virtual world information content. The physical information that is relatively difficult to experience in the real world space is based on science and technology such as computers. It implements simulation and processing, and superimposes the virtual information content to effectively apply it in the real world. In the process, it can be used by humans. Perceived by the senses to achieve a sensory experience beyond reality. After the real environment and the virtual object overlap, it can exist in the same picture and space at the same time. ^[2]

Augmented reality technology can not only effectively reflect the real world content, but also can promote the display of virtual information content. These delicate contents complement and superimpose each other. In visualized augmented reality, users need to make the real world and computer graphics coincide with each other on the basis of the helmet display. After the coincidence, the real world can be fully seen around it. The augmented reality technology mainly includes new technologies and methods such as multimedia and three-dimensional modeling and scene fusion. There is a significant difference between the information content provided by augmented reality and the information content that humans can perceive. ^[2]

Augmented Reality Development

The origin of AR technology can be traced back to the Sensorama Stimulator invented by Morton Heilig in the 1950s and 1960s. He is a filmmaker and inventor. He used his many years of filming experience to design a machine called Sensorama Stimulator. ^[3] SensoramaStimulator uses images, sounds, fragrances, and vibrations at the same time to make people feel like they are riding a motorcycle on the streets of Brooklyn, New York. This invention was very advanced at the time. Taking this as an opportunity, AR has also started its development history. ^[3]

Due to the subversive and revolutionary nature of AR technology, AR technology has received a lot of attention. As early as the 1990s, there were 3D games on the market. However, due to the high price of AR technology at the time, its own delays were long, and the computing capacity of the device was limited. These AR game products ended in failure. The first AR boom So it subsided. By 2014, after Facebook acquired Oculus for $ 2 billion, a similar AR fever hit again. In 2015 and 2016, 225 venture investments were made in the AR field, with an investment of 3.5 billion U.S. dollars. The original field has been expanded to many new fields, such as urban planning, virtual simulation teaching, surgical diagnosis and treatment, and cultural heritage protection. Wait. Today, immersive technologies such as AR and VR are rapidly developing, which has changed the way consumers, businesses and the digital world interact to a certain extent. Users expect a greater degree of migration from 2D to more immersive 3D, and get new experiences from 3D, including business, experience stores, robots, virtual assistants, area planning, monitoring, etc., people upgrade from using only language functions to include All-round experience including vision. In this development process, AR will surpass VR and better meet user needs. ^[3]

Key technologies for augmented reality

1.Track registration technology

In order to achieve the seamless superposition of virtual information and real scenes, this requires registration and registration of virtual information and real environment in a three-dimensional space position. This includes the user's spatial positioning tracking and the positioning of virtual objects in real space. The position of the camera of the mobile device and the virtual information needs to correspond, which needs to be achieved through tracking technology. Tracking registration technology first detects the feature points and contours of objects that need to be "enhanced". Tracking feature points automatically generates two-dimensional or three-dimensional coordinate information. The quality of tracking registration technology directly determines the success of augmented reality systems. Common tracking registration There are four methods: tracker-based registration, machine vision-based tracking registration, and wireless network-based hybrid tracking registration technology. ^[4]

2. Display technology

The display system of augmented reality technology is a relatively important content. In order to obtain a more realistic virtual system, which makes the convenience of practical applications continue to increase, the use of richer color displays is an important foundation. On this basis, the display contains Helmet displays and non-helmet display devices, and other related content, see-through helmets can provide users with relevant reverse fused scenarios. During the specific operation of these systems, the principles of operation and immersive helmets in the field of virtual reality, etc. The degree of similarity is relatively high. The interface and image that it interacts with the user are integrated, and a more realistic and effective environment is used to implement the form of a miniature camera to capture images of the external environment. When the computer image is effectively processed, it can be combined with the virtual and real environment. Blend together, and the images between the two can also be superimposed. On this basis, the optical see-through helmet display can use a transflective optical synthesizer installed in front of the user's eyes, which is fully integrated with the real environment. The real scene can be supported by the user on the basis of a half-lens, and meet User's related operation needs. ^[4]

3.Virtual object generation technology

When the augmented reality technology is applied, its goal is to make the relevant content of the virtual world superimposed in the real world, effectively promote the effective realization of the dynamic operation of objects based on the application of algorithm programs. The current generation of virtual objects is achieved on the basis of 3D modeling technology, which can fully reflect the reality of virtual objects. In the process of research and development of augmented reality dynamic models, it is necessary to be able to display objects in all directions and collectively. come out. In the process of generating virtual objects, natural interaction is one of the more important technical content. When it is implemented, it effectively assists the effective implementation of real technology to make information registration better. It uses image tags to monitor the external input content in real time. The operation efficiency of the augmented reality information can be improved, and the user can effectively realize the processing of the information content and extract the useful information content during the information processing. ^[4]

4.Interaction technology

Unlike in real life, augmented reality is the presentation of virtual things in reality, and interaction is to help virtual things prepare for better presentation in reality, so if you want to wait for a better AR experience, interaction is the key The highest priority. ^[5]

The interaction modes of AR devices are mainly divided into the following three types:

(1) Point selection in the real world for interaction is the most common type of interaction. For example, AR cards and graduation albums, which are currently popular, interact through the position of pictures. ^[5]

(2) Judging the specific posture or state of one or more things in space, these postures correspond to different commands. Users can arbitrarily change and use commands to interact, such as using different gestures to indicate different instructions. ^[5]

(3) Use special tools to interact. Google Earth, for example, uses something similar to a mouse to perform a series of operations to meet user requirements for AR interaction. ^[5]

5. Merge technology

The goal of augmented reality is to seamlessly combine virtual information with the input reality scene. In order to increase the reality experience of AR users, AR needs to have a strong sense of reality. In order to achieve this goal, not only the positioning of virtual things, but also The occlusion relationship between virtual things and real things needs to be considered, and there are four conditions: geometric consistency, model authenticity, lighting consistency, and hue consistency. These four are indispensable. The absence of any one will lead to the instability of AR effects. This seriously affects the AR experience. ^[5]

How Augmented Reality Works

Three main technical points of AR: three-dimensional registration (tracking registration technology), virtual reality fusion display, and human-computer interaction. The process is to first collect data from the real scene through the camera and sensors, and then analyze and reconstruct it through the processor, and then update the user in real time through the AR headset or the camera, gyroscope, sensors and other accessories on the smart mobile device. The data of the spatial position change in the real environment, so as to obtain the relative position of the virtual scene and the real scene, achieve the alignment of the coordinate system and perform the fusion calculation of the virtual scene and the real scene, and finally present the composite image to the user. Users can collect control signals through AR headsets or interactive accessories on smart mobile devices, such as microphones, eye trackers, infrared sensors, cameras, and sensors, and perform corresponding human-computer interaction and information updates to achieve augmented reality. Interaction. Among them, three-dimensional registration is the core of AR technology, that is, using two-dimensional or three-dimensional objects in the real scene as identifiers to match the virtual information with the actual scene information, that is, the position, size, and movement path of the virtual object and the real environment. Must be perfectly matched to reach the point where the false and the real come together. ^[6]

Augmented reality system components

The function of the augmented reality system mainly includes four key parts. Among them, the image acquisition processing module is to collect the video of the real environment, and then to the image

AR technology Image preprocessing; and the registration tracking positioning system is to track the target in the real scene, according to the change of the position of the target to obtain the camera's pose change in real time, so as to superimpose the virtual object to the real scene according to the correct spatial perspective The virtual information rendering system renders the virtual information after knowing the correct placement of the virtual object in the real environment; the virtual-real fusion display system overlays the rendered virtual information in the real environment and displays it. ^[7]

A complete augmented reality (AR) system is implemented by a set of tightly connected, real-time working hardware components and related software systems. There are three commonly used forms. ^[8]

(1) Based on computer monitor

In a computer monitor-based augmented reality (AR) implementation, real-world images captured by a camera are input into a computer, combined with a virtual scene generated by a computer graphics system, and output to a computer screen display. The user sees the final enhanced scene picture on the screen. This implementation is simple. ^[8]

(2) Video perspective

Video See-through HMD (Video See-through HMD) based on video synthesis technology used in video see-through augmented reality (AR) systems. ^[8]

(3) Optical see-through

Head-mounted displays (HMD) are widely used in augmented reality (AR) systems to enhance the visual immersion of users. According to the specific implementation principles, they can be divided into two categories, namely optical see-through HMD based on optical principles and video see-through HMD based on video synthesis technology. ^[8]

Optical see-through augmented reality (AR) systems have the advantages of simplicity, high resolution, and no visual aberrations, but they also have problems such as high positioning accuracy requirements, difficult delay matching, relatively narrow fields of view, and high prices. ^[8]

AR Applications

With the maturity of AR technology, AR is increasingly used in various industries, such as education, training, medical, design, advertising, etc. ^[6]

Education

With its rich interactivity, AR has injected new vitality into the development of children's education products. Children are characterized by liveliness, and educational products developed using AR technology are more suitable for children's physical and psychological characteristics. For example, AR books can be found everywhere on the market. For young children, the text description is too abstract. The combination of text and dynamic stereo images will allow children to quickly grasp new knowledge, and the rich interaction methods are more in line with the lively and active characteristics of children. Improved children's motivation to learn. AR is also playing an increasing role in school-age education. For example, some dangerous chemistry experiments, as well as esoteric mathematical and physical principles can be used by students to quickly master it. ^[6]

2.Health and Medical

In recent years, AR technology has also been increasingly used in medical education, patient analysis, and clinical treatment. Minimally invasive surgery is increasingly relying on AR and VR technology to reduce patient pain, reduce surgical costs and risks. In addition, in medical teaching, the application of AR and VR technology has made esoteric and difficult medical theories into three-dimensional and easy to understand, greatly improving the efficiency and quality of teaching. ^[6]

3. Advertising shopping

AR technology can help consumers more intuitively determine whether a product is suitable for them when shopping, so as to make more satisfactory choices. Users can easily see the effect of different furniture placed in the home through the software easily, which is convenient for users to choose. The software also has the function of saving and adding to the shopping cart. ^[6]

4. Show guide

AR technology is widely used in museums' descriptions of exhibits. This technology provides visitors with a guide to the exhibits by superimposing information such as virtual text, pictures, videos and other information on the exhibits. In addition, AR technology can also be applied to the restoration of cultural relics, that is, the original part of the cultural relics or the incomplete cultural relics will be used to perfectly integrate the restored part with the remaining part, so that visitors can understand the original appearance of the cultural relics and achieve immersive effects. ^[6]

5. Application in the field of information retrieval

When the user needs to have a clear understanding of the function and description of an item, the augmented reality technology will aggregate the relevant information of the item from different directions according to the user's needs and display it in the user's field of vision in real time. In the future, people can scan the face to identify the person s credit and some public information to prevent being deceived. The implementation of these technologies greatly reduces the chance of being deceived and facilitates users to work quickly and efficiently. ^[9]

6, applied to the field of industrial design interaction

The most special feature of augmented reality technology is its high degree of interactivity. It is used in industrial design and is mainly manifested as virtual interaction. Interaction technology is realized through gestures, clicks and other recognition. Virtual devices and products are displayed to designers and users In the past, it is also possible to implement virtual simulation through partial control, imitate assembly conditions or daily maintenance, disassembly and other tasks, and learn in virtual, reducing manufacturing waste and personnel training costs, greatly improving the design system and shortening the design time. Improve efficiency. ^[9]

VR&AR Augmented Reality VR & AR

VR Augmented reality VR

Virtual reality technology, referred to as VR technology for short, is a type of imaging technology that uses 3D interactive logic. The application time of virtual reality technology is short, so the core structure is mainly composed of environment simulation system, environment perception system and environment sensing system. Virtual reality technology, as the name suggests, is to bring users into a preset virtual space, and realize visual image stimulation through the virtual space experience, so as to achieve the purpose of 3D imaging technology application. Although the application of modern virtual reality technology is generally mature, it does not have the preset function of independent environment. It is necessary to control the imaging content through a connection with a computer, and a computer becomes a virtual space design. Therefore, the application of virtual implementation technology mainly plays the role of visual transmission and visual information transmission, so that the image information changes from two-dimensional space structure to three-dimensional Spatial structure transition to form a perfect image processing system, so that users can achieve the best image viewing experience. ^[10]

Augmented reality comparison

VR users have a small base, poor mobility, and a sense of isolation and immersion, so they are mainly focused on entertainment purposes. Entertainment revenue may account for two-thirds of the industry's revenue, with hardware accounting for about a quarter. Although VR will also have enterprise uses, it is much less than AR and smart glasses. VR e-commerce and advertising revenue will grow, but the size and fragmentation of the current user base has limited its development. ^[3]

Compared with VR, AR will reach more people because it is a seamless complement to people's daily lives. AR is a computer-generated virtual world superimposed on the real world. Various practical applications in medicine, education, and industry have proven that AR as a tool has a far-reaching impact on humans. Instead of creating a completely virtual world outside the real world like VR. Foreign analysts also believe that "AR" will become "a part of more routine mobile device applications." At the same time, the popularity and low cost of mobile AR will also help companies to adopt AR technology. Enterprise AR can grow steadily. By 2021, augmented reality technology will be used in manufacturing / resources, TMT, government (including military), retail, construction / real estate. , Healthcare, education, transportation, financial services, and utilities. ^[3]