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ISO 13406-2 is an ISO standard, with the full title "Ergonomic requirements for work with visual displays based on flat panels -- Part 2: Ergonomic requirements for flat panel displays". It is best known to end consumers for defining a series of flat-panel display "classes" with different numbers of permitted defects (or "dead pixels"). ISO 13406-2 also provides a classification of Viewing Direction Range Classes and Reflection Classes.
As part of an ISO standard, the classes are guidelines, and not mandatory. Where implemented, the interpretation of the standard by the panel or end product manufacturer and effects in terms of labeling of products, what class of panel is used, etc., can vary. Most flat-panel makers use this standard as the excuse for not accepting returns of defective flat-panels. Many customers argue that it's not honest in the makers' part to sell a product that most people wouldn't accept if they knew it had these defects. Also, there is little offer of Class I panels, that added to the fact that the price of these models is usually very high, make it difficult to buy a totally guaranteed product. One solution to this problem would be to sell these defected panels at a lower price than normal ones, clearly indicating the presence of such defects.
The ISO 13406-2:2001 standard has been withdrawn and revised by the ISO 9241-302, 303, 305 and 307:2008 standards.
The standard lists four classes of devices, where a device of a specified class may contain a certain maximum number of defective pixels. Three distinct types of defective pixels are described:
The table below shows the maximum number of allowed defects (per type) per 1 million pixels.
Class | Type 1 | Type 2 | Type 3 | Cluster with more than one type 1 or type 2 faults | Cluster of type 3 faults |
---|---|---|---|---|---|
I | 0 | 0 | 0 | 0 | 0 |
II | 2 | 2 | 5 | 0 | 2 |
III | 5 | 15 | 50 | 0 | 5 |
IV | 50 | 150 | 500 | 5 | 50 |
As of 2007 [update] , most manufacturers specify their products as Pixel Fault Class II. [1]
A computer monitor is an output device that displays information in pictorial or textual form. A discrete monitor comprises a visual display, support electronics, power supply, housing, electrical connectors, and external user controls.
A liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directly but instead use a backlight or reflector to produce images in color or monochrome.
Usability can be described as the capacity of a system to provide a condition for its users to perform the tasks safely, effectively, and efficiently while enjoying the experience. In software engineering, usability is the degree to which a software can be used by specified consumers to achieve quantified objectives with effectiveness, efficiency, and satisfaction in a quantified context of use.
Quality assurance (QA) is the term used in both manufacturing and service industries to describe the systematic efforts taken to assure that the product(s) delivered to customer(s) meet with the contractual and other agreed upon performance, design, reliability, and maintainability expectations of that customer. The core purpose of Quality Assurance is to prevent mistakes and defects in the development and production of both manufactured products, such as automobiles and shoes, and delivered services, such as automotive repair and athletic shoe design. Assuring quality and therefore avoiding problems and delays when delivering products or services to customers is what ISO 9000 defines as that "part of quality management focused on providing confidence that quality requirements will be fulfilled". This defect prevention aspect of quality assurance differs from the defect detection aspect of quality control and has been referred to as a shift left since it focuses on quality efforts earlier in product development and production and on avoiding defects in the first place rather than correcting them after the fact.
Infrared thermography (IRT), thermal video and/or thermal imaging, is a process where a thermal camera captures and creates an image of an object by using infrared radiation emitted from the object in a process, which are examples of infrared imaging science. Thermographic cameras usually detect radiation in the long-infrared range of the electromagnetic spectrum and produce images of that radiation, called thermograms. Since infrared radiation is emitted by all objects with a temperature above absolute zero according to the black body radiation law, thermography makes it possible to see one's environment with or without visible illumination. The amount of radiation emitted by an object increases with temperature; therefore, thermography allows one to see variations in temperature. When viewed through a thermal imaging camera, warm objects stand out well against cooler backgrounds; humans and other warm-blooded animals become easily visible against the environment, day or night. As a result, thermography is particularly useful to the military and other users of surveillance cameras.
An LCD projector is a type of video projector for displaying video, images or computer data on a screen or other flat surface. It is a modern equivalent of the slide projector or overhead projector. To display images, LCD projectors typically send light from a metal-halide lamp through a prism or series of dichroic filters that separates light to three polysilicon panels – one each for the red, green and blue components of the video signal. As polarized light passes through the panels, individual pixels can be opened to allow light to pass or closed to block the light. The combination of open and closed pixels can produce a wide range of colors and shades in the projected image.
On 2D displays, such as computer monitors and TVs, the display size or viewable image size (VIS) is the physical size of the area where pictures and videos are displayed. The size of a screen is usually described by the length of its diagonal, which is the distance between opposite corners, usually in inches. It is also sometimes called the physical image size to distinguish it from the "logical image size", which describes a screen's display resolution and is measured in pixels.
An inspection is, most generally, an organized examination or formal evaluation exercise. In engineering activities inspection involves the measurements, tests, and gauges applied to certain characteristics in regard to an object or activity. The results are usually compared to specified requirements and standards for determining whether the item or activity is in line with these targets, often with a Standard Inspection Procedure in place to ensure consistent checking. Inspections are usually non-destructive.
ISO 9241 is a multi-part standard from the International Organization for Standardization (ISO) covering ergonomics of human-computer interaction. It is managed by the ISO Technical Committee 159. It was originally titled Ergonomic requirements for office work with visual display terminals (VDTs). From 2006 onwards, the standards were retitled to the more generic Ergonomics of Human System Interaction.
User interface (UI) design or user interface engineering is the design of user interfaces for machines and software, such as computers, home appliances, mobile devices, and other electronic devices, with the focus on maximizing usability and the user experience. In computer or software design, user interface (UI) design primarily focuses on information architecture. It is the process of building interfaces that clearly communicate to the user what's important. UI design refers to graphical user interfaces and other forms of interface design. The goal of user interface design is to make the user's interaction as simple and efficient as possible, in terms of accomplishing user goals.
Specsmanship is the use of specifications or measurement results to suggest or establish putative superiority of one entity over, especially when it is inappropriate. It is commonly found in advertising of high fidelity audio equipment, automobiles, digital cameras, electronic display devices, and other merchandise.
A defective pixel is a pixel on a liquid crystal display (LCD) that is not functioning properly. The ISO standard ISO 13406-2 distinguishes between three different types of defective pixels, while hardware companies tend to have further distinguishing types.
The viewing cone refers to the effective viewing directions of an LCD display, as seen from the eye. This collection of angles resembles a cone. The concept has been introduced as an international standard ISO 13406-2, which defines it as the range of viewing directions that can safely be used for the intended task without "reduced visual performance". This standard describes a complex procedure which evaluates the viewing cone from measurements of luminance and chromaticity versus direction of observation. ISO 13406-2 introduces 4 viewing direction range classes, from a wide viewing cone, for many simultaneous observers, to the so-called "privacy display", with a severely limited viewing cone. Compliance routes for different display applications can now be found in the successor standard ISO 9241-300.
An electronic visual display is a display device that can display images, video, or text that is transmitted electronically. Electronic visual displays include television sets, computer monitors, and digital signage. They are ubiquitous in mobile computing applications like tablet computers, smartphones, and information appliances. Many electronic visual displays are informally referred to as screens.
Ergonomics, also known as human factors or human factors engineering (HFE), is the application of psychological and physiological principles to the engineering and design of products, processes, and systems. Primary goals of human factors engineering are to reduce human error, increase productivity and system availability, and enhance safety, health and comfort with a specific focus on the interaction between the human and equipment.