Computer Fundamentals 简明教程

Computer - Output Devices

输出设备是一种硬件设备,用于以文本、音频、视频、计算机屏幕上的视觉效果或纸质印刷品的形式向用户显示处理结果。输出设备主要分为音频输出设备、视觉输出设备、视音频输出设备和基于打印的输出设备。可以将不同的输出设备连接到计算机系统以检索输出,具体取决于输出类型和要求。

An output device is a hardware device that is used to show the processed results to the user in the form of text, audio, video, visuals on a computer screen or a printed hard copy on paper. The output devices are mainly categorised as audio output devices, visual output devices, audio-video output devices, and print-based output devices. Different output devices can be connected to computer systems to retrieve the output, based on the type of output and requirements.

以下是计算机中使用的一些重要输出设备。

Following are some of the important output devices used in a computer.

  1. Monitors

  2. Graphic Plotter

  3. Printer

  4. Speakers

  5. Headphones

  6. Projector

  7. GPS

Monitors

显示器也被称为 Visual Display Unit (VDU) ,是计算机的输出设备。它是最流行的输出设备,看起来像电视屏幕,以文本、音频、视频和图像的形式显示输出。总体而言,它通过视觉效果产生输出,将用户与系统连接起来。图像数据由称为像素的小点组成,这些小点以矩形形式排列。图像的清晰度取决于像素数量。

Monitors also known as Visual Display Unit (VDU), is an output device of a computer. It is the most popular output device which looks like a TV screen and shows the output in the form of text, audio, video and images. Overall, it produces output with visual effects to connect the user with the system. Images data form tiny dots, called pixels that are arranged in a rectangular form. The sharpness of the image depends upon the number of pixels.

用于显示器的有两种观看屏幕。

There are two kinds of viewing screens used for monitors.

  1. Cathode-Ray Tube (CRT)

  2. Flat-Panel Display

Cathode-Ray Tube (CRT) Monitor

CRT 显示器由称为像素的小像素组成。像素越小,图像清晰度或分辨率就越好。需要一个以上的点亮像素才能形成一个完整的字符,比如单词“帮助”中的字母“e”。

The CRT display is made up of small picture elements called pixels. The smaller the pixels, the better the image clarity or resolution. It takes more than one illuminated pixel to form a whole character, such as the letter ‘e’ in the word help.

crt monitor

屏幕上一次只能显示有限数量的字符。屏幕可以划分为一系列字符框 - 屏幕上可以放置标准字符的固定位置。大多数屏幕能够水平显示 80 个字符的数据,垂直显示 25 行数据。

A finite number of characters can be displayed on a screen at once. The screen can be divided into a series of character boxes - a fixed location on the screen where a standard character can be placed. Most screens are capable of displaying 80 characters of data horizontally and 25 lines vertically.

CRT 显示器的关键组件如下 −

The key components of a CRT Monitor are as follows −

  1. Electron Guns − Produces beams of electrons to display images

  2. Phosphorescent Screen − Once electrons hit on phosphor-coated screen, it glows and makes visibility

  3. Circuit Board − Provides connectivity for external circuitry

  4. Deflection Yoke − It deflects the electron beam in precise patterns

  5. Produces output with visual effects.

  6. It has good resolutions which ensure proper visibility of image-related outputs.

  7. No motion blur due to instant response time.

  8. It can display multiple resolutions without scaling artefacts.

  9. It has high refresh rates which reduces flicker and eye strain.

  10. Large in Size

  11. Carries high weight

  12. A lot of power consumption

  13. Produces heat

Flat-Panel Display Monitor

平板显示器是指一类相比于阴极射线管,总体积、重量和功率需求都降低了的视频设备。你可以将它们挂在墙上,或戴在手腕上。平板显示器的当前用途包括计算器、视频游戏、显示器、笔记本电脑和图形显示设备。

The flat-panel display refers to a class of video devices that have reduced volume, weight and power requirements in comparison to the CRT. You can hang them on walls or wear them on your wrists. Current uses of flat-panel displays include calculators, video games, monitors, laptop computers, and graphics displays.

flat monitor

平板显示器分为两种类 −

The flat-panel display is divided into two categories −

  1. Emissive Displays − Emissive displays are devices that convert electrical energy into light. For example, plasma panels and LED (Light-Emitting Diodes).

  2. Non-Emissive Displays − Non-emissive displays use optical effects to convert sunlight or light from some other source into graphics patterns. For example, LCD (Liquid-Crystal Device).

平板显示器监视器的关键组件如下 −

The key components of a Flat-Panel Display Monitor are as follows −

  1. Liquid Crystal Display (LCD) − It is positioned between two layers of glass or plastic and modulates light to create images.

  2. Light Emitting Diode (LED) − it emits light and improves colour and contrast.

  3. Plasma Display Panel (PDP) − It contains small cells with phosphor coated to emit light.

  4. Quantum Dot Display − It contains quantum dots to enhance colour accuracy.

平板显示器监视器的一些主要优点如下 −

Some of the key advantages of Flat-Panel Display Monitor are as follows −

  1. Smaller in size makes it easy to mount and transport.

  2. It consumes less power.

  3. It has higher resolutions which makes good picture quality.

  4. It makes users comfortable to get connected for a longer period and reduces eye strain.

  5. Available in different sizes.

  6. Expensive as compared to CRT monitors.

  7. Its resolution is not up to mark as compared to CRT.

  8. It is a soft covering which may damage and be difficult to clean.

Graphic Plotter

绘图仪是一种打印机,它从计算机接收指令,使用一个或多个自动笔在纸上绘制线条图。与标准打印机不同,绘图仪可以直接从矢量图形文件或命令创建连续的点对点线条。计算机图形和工程应用程序采用图形绘图仪在纸张或其他介质上创建高质量、准确且详细的图形或绘图。它可以准确地绘制连续线,适用于矢量绘图,与标准打印机不同。图形绘图仪的主要功能如下−

A plotter, which is a type of printer, receives instructions from a computer to produce line drawings on paper using one or more automated pens. In contrast to a standard printer, a plotter can create uninterrupted point-to-point lines directly from vector graphic files or commands. Computer graphics and engineering applications employ graphic plotters to create high-quality, accurate, and detailed drawings or plots on paper or other media. It draws continuous lines accurately and is suited for vector drawings, unlike a standard printer. Key features of graphic plotters are as −

  1. Vector Graphics − Vector graphics allow graphic plotters to create lines and shapes precisely using continuous points instead of dots like raster printers.

  2. Pen or Pen-Like Tool − A pen or similar instrument is drawn on paper for graphic plotters. The pen may move X and Y on a moveable arm to draw complicated shapes.

  3. Applications − Graphic plotters are employed in engineering, architecture, cartography, and textile design. They were popular for technical drawings and diagrams before digital.

graphic plotter

矢量图形绘图仪输出准确且详细的图纸。即使数字印刷已使其不那么普及,它们仍用于需要准确和高质量输出的行业和应用中。

A vector graphics plotter outputs accurate and detailed drawings. They are still used in sectors and applications that need accuracy and high-quality output, even if digital printing has made them less widespread.

Components of Graphic Plotters

图形绘图仪的关键组件如下−

The key components of a Graphic Plotter are as follows −

  1. Plotter Head − A plotter head contains multiple pens of different colours to draw images.

  2. Plotting Surface − It is used to hold and feed paper.

  3. Microcontroller − Controls the plotting process and interprets commands.

  4. Interfaces − It provides interfaces to connect USB, Ethernet, or wireless connections.

  5. Memory − A device used to Store plotting instructions to process temporarily.

Types of plotters

  1. Pen Plotters − It uses vector graphics and line drawings.

  2. Drum plotters − A drum plotter is a device that uses a rotating drum to draw on paper. The drum revolves to create one direction of the plot, while the pens move to create the other direction.

  3. Flatbed plotters − Flatbed plotters are used to draw on paper placed on a flat surface.

  4. Electrostatic plotters − This printer draws on negatively charged paper with positively charged toner.

  5. Inkjet plotters − The printer uses vector graphic technology to control the movement of the pen plotters, which in turn drop ink beads of different colours onto the drawing surface.

Advantages

图形绘图仪的部分主要优势如下−

Some of the key advantages of Graphic Plotters are as follows −

  1. High Resolution − It has good resolution which opens it for CAD drawings.

  2. Colour Representation − It automatically sets colour matching in designs.

  3. Large Screen Size − It provides appropriate space to view large drawings.

  4. Software Compatibility − It is compatible with CAD software, graphic design, and related tools.

  5. Preview Functionality − A user can preview plots on the monitor to reduce errors and enhance accuracy.

  6. Editing Tools − Multiple editing tools are available for graphics before plotting.

Printers

打印机是一种输出设备,用于在纸上打印已处理的数据。它是较流行的输出设备之一。打印的信息通常被称为硬拷贝,因为它实际存在,并且比仅在显示设备上显示的内容更持久。打印机在生成数字文档和图像的硬拷贝中扮演着至关重要的角色,并且有不同类型可供选择,以迎合特定目的和环境。它们满足不同的用户需求,提供诸如顶级照片打印、快速文档输出以及创建三维对象等功能,使其适用于家庭、办公室或工业用途。

A printer is an output device, which is used to print processed data on paper. It is one of the most popular output devices. The information that is printed is commonly referred to as hard copy because it physically exists and is a more enduring form of output than what is displayed on a VDU. Printers play a crucial role in generating hard copies of digital documents and images and are available in different types tailored to specific purposes and settings. They cater to diverse user requirements, offering features such as top-notch photo printing, speedy document output, and the ability to create three-dimensional objects, making them suitable for home, office, or industrial use.

Types of Printer

不同类型的打印机在下列图像中分类

Different types of Printers are categorised in the following image

types of printer

Impact Printers

击打式打印机通过击打色带上的字符来进行打印,然后将色带压在纸张上。

Impact printers print the characters by striking them on the ribbon, which is then pressed on the paper.

击打式打印机的特性如下 −

Characteristics of Impact Printers are the following −

  1. Very low consumable costs

  2. Very noisy

  3. Useful for bulk printing due to low cost

  4. There is physical contact with the paper to produce an image

通常,冲击式打印机分为以下两种类型:

Generally, Impact printers are of two types −

  1. Character printers

  2. Line printers

字符打印机是逐个打印字符的打印机。这些打印机保留单个字符,直到准备好打印它们为止。字符打印机不一次打印一行,而是逐个打印字符。当前,由于这些打印机速度受限,并且只能打印文本,因此很少见。

Character printers are the printers which print one character at a time. A printer that holds individual characters until it is ready to print them. Instead of printing one line at a time, a character printer prints one character at a time. Nowadays, these printers are not commonly used due to speed limitations and their ability to only print text.

Types of Character Printers

Types of Character Printers

  1. Dot Matrix Printer(DMP)

  2. Daisy Wheel

在市场中,最流行的打印机之一是点阵打印机。这些打印机因其易于打印和价格实惠而流行。所打印的每个字符都是由点模式组成的,而打印头由一个大小为 (5*7, 7*9, 9*7 或 9*9) 的针组组成,它们出来形成一个字符,这就是为什么它被称为点阵打印机的原因。

In the market, one of the most popular printers is Dot Matrix Printer. These printers are popular because of their ease of printing and economical price. Each character printed is in the form of a pattern of dots and the head consists of a Matrix of Pins of size (5*7, 7*9, 9*7 or 9*9) which come out to form a character which is why it is called Dot Matrix Printer.

dot matrix printer
  1. Inexpensive

  2. Durable

  3. Widely Used

  4. Able to print on multi-part forms

  5. Low Operating Costs

  6. Reliable

  7. Other language characters can be printed

  8. Slow Speed

  9. Poor Quality

菊花轮打印机是一种冲击式打印机,它利用一个旋转盘(称为“菊花轮”),其中含有预制字符,这些字符凸印在它的“花瓣”上。在打印过程中,打印机挑选合适的纸花,将它压到色带,然后将它压到纸上,生成高质量的文本。

A daisy wheel printer is an impact printer that utilizes a spinning disk, known as the "daisy wheel," which contains pre-formed characters embossed on its "petals." During printing, the printer picks the appropriate petal, impacts it against an ink ribbon, and then onto the paper to generate high-quality text.

打印头安装在一个轮子上,且字符对应的针就像一朵菊花的花瓣,这就是为什么它被称为菊花轮打印机的原因。这些打印机通常用于对质量有极高要求的办公文字处理,在这些场景下,需要邮寄极少量信件。在激光打印机和喷墨打印机面世之前,菊花轮打印机在 20 世纪 70 和 80 年代通常用于文字处理。

The head is lying on a wheel and pins corresponding to characters are like petals of Daisy (flower) which is why it is called Daisy Wheel Printer. These printers are generally used for word processing in offices that require a few letters to be sent here and there with very nice quality. In the 1970s and 1980s, daisy wheel printers were commonly utilized for word processing before the introduction of laser and inkjet printers.

daisy wheel printer
  1. It produces High-Quality Text so more suitable for professional documents

  2. More reliable than DMP

  3. Better quality

  4. Fonts of character can be easily changed

  5. Durable so it has a long lifespan

  6. Each character is pre-formed which shows its consistent print quality

  7. Slower than DMP

  8. Limited to Text

  9. Noisy

  10. More expensive than DMP

  11. Changes in fonts or styles need physical changes on the daisy wheel

行打印机是每次打印一行的打印机。行打印机是专门设计的、专门用于获取高速、大容量打印(主要是文本)的专用冲击式打印机。它们仍然在某些对速度和耐久性要求极高的应用场景中发挥作用。它们一次打印一整行的文本的功能将它们与其他冲击式打印机区分开来,使其非常适用于需要快速、一致创建文档的应用场景。

Line printers are the printers which print one line at a time. Line printers are specialised impact printers which are specifically designed to get high-speed, high-volume printing, primarily for text. These are still useful in certain applications where speed and durability are critical. Their capacity to print a complete line of text at once distinguishes them from other impact printers, making them excellent for applications requiring quick and consistent document creation.

line printer
  1. Drum Printer

  2. Chain Printer

这款打印机形状像个鼓,因此被称作鼓式打印机。鼓面会被分成若干条轨道。轨道的总数等于纸张的尺寸,也即 132 个字符宽的纸张,该打印机的鼓会有 132 条轨道。每个轨道上都浮雕了一组字符。市面上提供的不同字符集包括 48 字符集、64 字符集和 96 字符集。鼓旋转一圈就能打印出一行。鼓式打印机速度很快,每分钟可以打印 300 至 2000 行。

This printer is like a drum in shape hence it is called a drum printer. The surface of the drum is divided into several tracks. Total tracks are equal to the size of the paper, i.e. for a paper width of 132 characters, the drum will have 132 tracks. A character set is embossed on the track. Different character sets available in the market are 48 character sets, 64 and 96 characters set. One rotation of drum prints one line. Drum printers are fast and can print 300 to 2000 lines per minute.

  1. Very high speed

  2. Low cost

  3. Durable so they can run a long life

  4. Able to handle large print volumes

  5. Provides good printing quality

  6. Very expensive

  7. Characters fonts cannot be changed

链式打印机是一款高速行式打印机,利用旋转链条机构在纸张上打印字符。链式打印机在需要大量打印的大型数据中心和商业环境中广泛使用。它们以能够快速而高效地处理大量打印作业而闻名。这种打印机使用一组字符集;因此,被称为链式打印机。标准字符集可能包含 48 个、64 个或 96 个字符。

A chain printer is a high-speed line printer with a revolving chain mechanism that prints characters on paper. Chain printers were widely used in large data centres and business settings where high-volume printing was required. They are well-known for their ability to handle huge print jobs quickly and efficiently. In this printer, a chain of character sets is used; hence it is called a Chain Printer. A standard character set may have 48, 64, or 96 characters.

  1. Character fonts can easily be changed

  2. Able to print hundreds to thousands of lines per minute

  3. Durable

  4. Different languages can be used with the same printer

  5. Cost-effective for printing large quantities of text.

  6. Noisy

  7. Limited Graphics

  8. Limited with fixed fonts and styles

Non-impact Printers

非击打式打印机在打印字符时不会使用色带。这些打印机一次打印一整页,因此也称为页面打印机。

Non-impact printers print the characters without using the ribbon. These printers print a complete page at a time, thus they are also called Page Printers.

这类打印机分为两种 −

These printers are of two types −

  1. Laser Printers

  2. Inkjet Printers

  3. Faster than impact printers

  4. They are not noisy

  5. High quality

  6. Supports many fonts and different character sizes

它们是非冲击页面打印机。它们使用激光灯来产生点,从而形成要打印在页面上的字符。

These are non-impact page printers. They use laser lights to produce the dots needed to form the characters to be printed on a page.

laser printer
  1. Very high speed

  2. Very high-quality output

  3. Good graphics quality

  4. Supports many fonts and different character sizes

  5. Expensive

  6. Cannot be used to produce multiple copies of a document in a single printing

喷墨打印机是非击打式字符打印机,基于相对较新的一项技术。它们通过将小墨滴喷洒到纸张上来打印字符。喷墨打印机生成的输出质量高,功能齐全。

Inkjet printers are non-impact character printers based on a relatively new technology. They print characters by spraying small drops of ink onto paper. Inkjet printers produce high-quality output with presentable features.

inkjet printer

它们发出的噪音较小,因为无需敲击,并且有许多可用的打印模式样式。还可以进行彩色打印。某些型号的喷墨打印机还可以生成多份打印副本。

They make less noise because no hammering is done and these have many styles of printing modes available. Color printing is also possible. Some models of Inkjet printers can produce multiple copies of printing also.

  1. High-quality printing

  2. More reliable

  3. Expensive as the cost per page is high

  4. Slow as compared to laser printer

Speakers

扬声器是标准输出设备,用于在可测距离内清晰地听到声音。它们通过声音连接器直接连接到计算机,而另一些则可以连接到任何声音系统。扬声器的主要目的是提供音频输出并使用户能够听到最终声音。

Speakers are standard output devices that are used to hear sound clearly from a measurable distance. These are connected to the computer through sound connectors directly while others can be linked to any sound system. The primary purpose of speakers is to deliver audio output and enable users to listen to the resulting sound.

speakers

Components of a Speakers

扬声器的一些关键组件如下:

Some of the key components of speakers are as follows −

  1. Magnet − It is an essential component fixed to speakers to create a magnetic field.

  2. Diaphragm (Cone) − It is made with paper, plastic and metal; it is used to create sound waves.

  3. Voice Coil − The diaphragm is connected to a voice coil of wire, which is placed in the magnetic field of the magnet.

  4. Suspension − This contains the spider and the surround. The spider keeps the voice coil centred in the magnetic gap and the surround links the diaphragm to the speaker frame and allows it to move freely.

How does the speaker work?

扬声器是将电磁波转变为声波的电磁波。计算机向扬声器提供音频输入。此输入可能是模拟或数字的。当音频信号通过音圈时,音圈会产生交变磁场。然后,此磁场与永磁铁的稳定磁场相互作用。模拟扬声器仅仅放大电磁信号以产生声波。声波是模拟信号。因此,数字扬声器必须将数字输入转换为模拟信号,然后才能产生可以作为输出传输的声波。

Speakers are electromagnetic waves that transform electromagnetic waves into sound waves. The computer supplies audio input to the speakers. This input may be analogue or digital. The voice coil generates an alternating magnetic field when the audio signal passes through it. This magnetic field then interacts with the stable magnetic field of the permanent magnet. Analogue speakers merely amplify electromagnetic signals to generate sound waves. Sound waves are analogue signals. Thus, digital speakers must convert the digital input to an analogue signal before producing a sound wave that can be transmitted as an output.

说话者使用语音命令来控制一个软件程序。电脑音箱是一种连接到计算机系统并产生声音的硬件。电脑的声卡包含用来从电脑音箱中产生声音的信号。

A speaker uses vocal commands to control a software programme. A computer speaker is hardware that connects to a computer system and produces sound. The computer’s sound card contains the signal utilised to generate sound from a computer speaker.

Types of speakers

以下是一些常用的音箱类型:

Some common types of speakers are as follows −

  1. Electrostatic speaker − An electrostatic speaker contains an electrically charged diaphragm which is positioned between two conductive plates. The electrical signal causes the diaphragm to move, which generates sound.

  2. Piezoelectric Speakers − These speakers use materials that change their shape when an electric field is applied and then create sound waves.

  3. Planar Magnetic Speakers − These speakers are similar to dynamic speakers, except they have a small, flat diaphragm and a voice coil that moves within a magnetic field.

  4. Subwoofers − Subwoofers produce very low-frequency sound, ranging from 20 to 200 Hz. The subwoofer is a speaker that can be oriented in any direction. These are specifically designed to produce low-frequency sounds (bass). Usually, they are used in Home theatre systems and car audio systems.

  5. Dynamic speaker − Dynamic speakers are often equipped with one or more woofer drivers. These have one or more tweeter drivers and are known for producing low-frequency sound.

  6. Bluetooth speakers − It’s a wireless speaker which is portable. A Bluetooth speaker produces high-quality audio.

speakers1
  1. Horn Speakers − These speakers produce horns to amplify sound; generally used by drivers.

Headphones

耳机是小型的扬声器,专门设计用于塞进耳机的耳罩或耳塞中。这些扬声器与较大的扬声器遵循相同的原理,但专门用于近距离聆听和个人音频欣赏。

Headphones are small-sized speakers which are specifically designed to fit into the earcups of headphones or earbuds. These speakers operate on the same principles as larger speakers but are tailored for listening at close range and for personal audio enjoyment.

Advantages

耳机扬声器的一些主要优点如下:

Some of the key advantages of headphone speakers are as follows −

  1. Produces better sound quality for personal use

  2. Users hear ambient sounds

  3. Relatively inexpensive

  4. Widely available

  5. Excellent for reproducing high frequencies

  6. Compact size

  7. Lower power requirements

Projector

投影仪是一种由光供电的输出设备,被称为投影仪。它有效地显示由计算机设备生成的处理结果,并用于在投影屏幕上展示图像。投影仪可以显示大量视觉内容,用于专业展示和家庭娱乐。

A projector is an output device powered by light is known as a projector. It effectively displays processed results generated by a computer device and is used to showcase images on a projection screen. Projectors can display large amounts of visual content for professional presentations and home entertainment.

Types of projector

以下是一些常用的投影仪类型:

Some common types of projectors are as follows −

  1. Cathode Ray Tube − It is a video projector which employs CRT to produce pictures. A lens is used to focus and enlarge the output to show on the screen.

  2. Liquid Crystal Display − LCD projectors use liquid crystals to display images, data, or videos. LCD projector is extensively used in business seminars, presentations, and meetings. These are more popular than other projectors as they have superb colour reproduction and lower manufacturing costs.

  3. Digital Light Processing − DLP projectors are used for front and back projection. A Three-chip DLP projector can output over 35 trillion colours, and display visuals more realistic and lifelike than one-chip models. It is used in companies and classrooms as a front projector and in TV as a rear projector.

Advantages

投影仪的一些主要优点如下:

Some key advantages of projectors are as follows −

  1. Effective visual projection − A projector displays visuals effectively on screen which bounds the audience.

  2. Portability − A user can carry it comfortably.

  3. Connectivity − It can easily connect in offices, seminar halls, or rooms.

  4. Applications − It is most widely used in businesses, education, and meetings to showcase their presentations.

  5. Entertainment − Most widely used to watch movies and play games.

  6. Resolution and Brightness − Used for events, advertising, and digital signage

GPS

GPS,即“全球定位系统”,是一种基于无线电的卫星导航系统,由一个称为星座的不同卫星网络组成。全球定位系统(GPS)可以使用无线电波确定精确的位置。用户会向卫星发送无线电信号,卫星会收集时间、位置、速度和其他变量等数据,并将其传输到计算机进行处理。用户可以使用这些信息来决策。

GPS, which stands for "Global Positioning System," is a radio-based satellite navigation system and is comprised of a network of different satellites called a constellation. The Global Positioning System (GPS) can determine a precise position using radio waves. The user transmits a radio signal to the satellites, which collect data such as time, location, speed, and other variables and transfer it to the computer for processing. Users can use this information to make decisions.

Advantages of GPS

以下是 GPS 的一些主要优势 −

Some key advantages of GPS are as follows −

  1. Accuracy − The accuracy of the location data is important, especially for applications such as aviation and marine navigation. Higher precision is essential in these applications. The accuracy of the location data is of great importance thus greater precision is essential for uses such as aviation and marine navigation.

  2. Display Quality − The screen’s resolution and readability are crucial, particularly when using outdoor devices in bright sunlight.

  3. Map Coverage and Updates − Maps for various areas and how easy it is to update them.

  4. Durability − Water, dust, and shock resistance are crucial for GPS devices used outdoors and in marine environments.

  5. Additional Features − Features such as planning routes, receiving real-time traffic updates, tracking fitness, and offering specialized marine and aviation functions.