2D & 3D Scanners

Two-Dimensional Scanners

Two-dimensional scanners convert physical documents into digital files. Scanners come in flatbed and handheld form. Many printers have built-in flatbed scanners.

How does it work?

A bright strip light illuminates and scans across the document.
The scanner creates a digital image based on the amount of light reflected from the document.
Optical character recognition (OCR) software installed on a computer can convert scanned images into editable text.

Applications

2D scanners are used to convert a physical version of a document into a digital form for storage, distribution, or editing.
- For example, airport staff will scan your passport in order to check its validity before you can fly.
Specialist scanners can convert old format material such as film negatives into digital files.

Advantages of 2D scanners

Flatbed scanners produce high-quality images.
Images once digitised can be enhanced with a graphics application like Photoshop.
Digital copies of documents can be sent electronically, stored securely, or edited.

Disadvantages of 2D scanners

Scanned documents can take a lot of computer memory to store.
Images lose some quality in the scanning and digitising process.
Flatbed scanners take up a large amount of space on a desk compared to handheld scanners.

Three-Dimensional Scanners

A three-dimensional scanner creates a digital 3D model of an object using electromagnetic waves. 3D scanners work by scanning from different positions around the object.

How does it work?

An object is scanned along three axes using lasers, light, radio waves or X-rays.
Some 3D scanners scan through thin slices of the object by using waves with certain frequencies to look inside objects.
- These scanners typically use gamma, radio and X-rays.
The scanned images are then edited in computer-aided design (CAD) software.
This allows the object itself to be duplicated using a 3D printer.

Applications

3D scanners have many uses, including:
- Airport security screenings to check for restricted items.
- Capturing the physical measurements of an object.
- Obtaining biometric data for medical treatments or identification.
- Creating digital characters based on real human attributes.

Advantages of 3D scanners

3D scanners are a noninvasive way of searching through clothing.
3D scanning provides accurate measurements to create computer models.
3D scanners can easily measure and catalogue unusually shaped objects.

Disadvantages of 3D scanners

Some 3D scanners are typically large, sometimes as big as a wardrobe!
Repeated exposure to X-rays in medical scanners can be harmful to the operator of the scanner.
3D scanners are expensive.

1Computer Systems

1.1Data Representation

1.1.1Binary Numbers

1.1.2Negative Binary Numbers

1.1.3Hexadecimal

1.1.4Using Hexadecimal

1.1.5Converting Binary & Hexadecimal

1.1.6Converting Denary & Hexadecimal

1.1.7Capacity

1.1.8Calculating Capacity Requirements

1.1.9Binary in Computer Systems

1.1.10Data Compression

1.1.11Run Length Encoding

1.1.12File Formats

1.2Data Transmission

1.2.1Packet Switching

1.2.2Data Transmission

1.2.3Universal Serial Bus (USB)

1.2.4Parity Check

1.2.5Checksum & Echo Checks

1.2.6Encryption

1.3Hardware

1.4Software

1.4.1Operating Systems

1.4.2Interrupts

1.4.3High-Level Languages

1.4.4Low-Level Languages

1.5The Internet & its Uses

1.5.1The Internet

1.5.2Uniform Resource Locators (URLs)

1.5.3DNS

1.5.4HTML

1.5.5Cookies

1.5.6Web Hosting

1.5.7Digital Currency

1.6Cyber Security

1.6.1Forms of Attack

1.6.2Penetration Testing

1.6.3Types of Malware

1.6.4How Malware Spreads

1.6.5Protecting Against Malware

1.6.6Information Security

1.6.7Structured Query Language (SQL) Injection

1.6.8Firewalls

1.6.9Authentication: User Access Levels

1.6.10Authentication: Passwords

1.6.11Social Engineering

1.6.12Phishing

1.6.13Denial of Service Attacks

1.7Automated & Emerging Technologies

1.7.1Automated Systems

1.7.2Robotics

1.7.3Artificial Intelligence

2Algorithms, Programming & Logic

2.1Algorithm Design & Problem Solving

2.1.1Computational Thinking - Abstraction

2.1.2Computational Thinking - Decomposition

2.1.3Computational Thinking - Algorithmic Thinking

2.1.4Pseudocode

2.1.5Flow Diagrams

2.1.6Interpreting, Correcting & Completing Algorithm

2.1.7Correcting Algorithms

2.1.8Completing Algorithms

2.1.9Testing

2.1.10Types of Testing

2.1.11Test Plans

2.1.12Validation & Sanitation

2.1.13Authentication & Contingencies

2.2Programming

2.2.1Programming Fundamentals - Variables & Constants

2.2.2Programming Fundamentals - Comments

2.2.3Programming Fundamentals - Input & Output

2.2.4Data Types

2.2.5Casting

2.2.6Controlling Program Flow - Sequence

2.2.7Controlling Program Flow - Selection

2.2.8Controlling Program Flow - Iteration

2.2.9Modularity - Subroutines

2.2.10Modularity - Scope

2.2.11Arrays

2.3Databases

2.3.1Structuring Data - Records

2.3.2Structuring Data - Databases

2.3.3SQL

2.4Boolean Logic

2.4.1Binary Systems

2.4.2Logic Circuits

2.4.3Truth Tables

2.4.4Evaluating Expressions

2.4.5Boolean Operators

2.4.6End of Topic Test - Logic

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