PERCOCO Questions - PDF

# PERCOCO (questions n.45) ## 1) How does the eye work? The eye collects light coming from the environment, regulates its intensity through the iris, focuses it to form an image through a system of lenses and transforms this image that passes through the optic nerve to be sent directly to the brain...

# PERCOCO (questions n.45) ## 1) How does the eye work? The eye collects light coming from the environment, regulates its intensity through the iris, focuses it to form an image through a system of lenses and transforms this image that passes through the optic nerve to be sent directly to the brain. ## 2) How is the retina structured? It is a thin layer of cells in which a peripheral zone (responsible for the field of vision) and a central zone represented by the macula lutea (responsible for visual acuity or visus) can be distinguished. ## 3) What is the function of the retina? The distorted and inverted image is projected onto the curved, two-dimensional surface of the retina which behaves like a transducer between the energy of photons and the signal transmitted through action potentials. It also perceives colours (cones) and provides precise information about the space surrounding us. ## 4) What is scotopic vision? Night vision due to the rods. ## 5) What is the visual cycle? A series of chemical reactions that take place in the cones and rods and allow the light signal to be transduced into an electrical signal sent to the brain. ## 6) What is the real organ of vision? The brain, occipital lobe - Brodmann areas n.17-18-19, processes three-dimensional images. ## 7) Where can the image not be perceived? In a blind spot present in both retinas. ## 8) What is visual function? It includes numerous specific perceptual abilities such as visual acuity, field of vision, colour recognition, glare resistance, depth perception and movement perception. ## 9) What are the two main perceptual abilities? Visual acuity (visus or distinct central vision) and field of vision (indistinct peripheral vision). ## 10) What is visual acuity? Distinct central vision, that is the ability to recognize an object in detail when it is fixed. ## 11) What is the field of vision? It is identified as - indistinct peripheral vision - and is the ability to perceive, indistinctly, the objects that make up the environment in the center of which the fixed object is located. ## 12) What is visual impairment? It consists in the reduction of the sensory function due to damage to the visual system. ## 13) What is partial blindness? A visus below 1/20. ## 14) What is low vision? The presence of incomplete visual function resulting from a visual impairment. ## 15) How can low vision be distinguished according to visus? - severe low vision (visus between 1/20 and 1/10) with a field of vision reduction of 50-60% - moderate low vision (visus between 1/10 and 2/10) with a field of vision reduction of 30-50% - mild low vision (visus between 2/10 and 3/10) with a field of vision reduction of 10-30%. ## 16) What tools are used in low vision? Video magnifiers, readers, PCs and smartphones. ## 17) How many types of video magnifiers are there? There are two types of video magnifiers: desktop and portable. ## 18) What are the components and how does a desktop video magnifier work? It has a carriage on which the paper is placed, an arm, lights, keys and a camera, it allows to enlarge printed documents in black but also hand-written documents directly visible on the monitor, changes the brightness, the contrast, zoom and allows different combinations of colors of characters and background. ## 19) What else can a desktop video magnifier be used for? For writing. ## 20) How does a portable video magnifier work? It has the shape of a tablet with a built-in screen, lights and cameras, it magnifies objects at a distance. It is possible to save, use the contrast and brightness, change colors, it is possible to magnify a two-dimensional and three-dimensional object. Photos can be taken and zooming can be varied. ## 21) Can a portable video magnifier be used for writing? No, because it is not practical as it requires a fixed support. ## 22) How does the PC work? It is a versatile tool that is useful for both visually impaired and blind users. It has various hardware components, QWERTY keyboard (input) with the hyphen in relief (key J) as a reference point for placing the hands (10 fingers) and software components for accessibility (see window for magnifying glass, mouse pointer modification, characters, brightness, contrast and colors). ## 23) What is the function of a screen reader? Reading the screen, websites need to be properly designed for better usability, for documents it is not enough to scan (image) for reading through speech synthesis, but it is necessary to use the optical character recognition (OCR) function obviously only on black printing (printed documents). ## 24) What is ICR (Intelligent Character Recognition)? The recognition of hand-written text in print, it can be considered an evolution and a differentiation of OCR which instead only recognizes printed characters. ## 25) What is the screen reader used in Microsoft operating systems (Windows)? *JAWS* whose license is not free, while Narrator and NVDA are free. ## 26) What is VoiceOver? VoiceOver is a built-in screen reader (screen reader) for IOS operating systems - apple, it reads what is written on the screen, to activate it from the keyboard (F5 key) also present on the smartphone with reading also of printed texts. ## 27) What is a mini audiobook ? It is composed of a base, an arm and a camera. It has vocal and manual commands. It saves in the order of the scan. It is portable; the language can be varied, files can be imported and exported. The text must be written in black and without abrasions (not by hand) for the purpose of reading through a speech synthesizer. ## 28) How is a Braille tablet composed? It can have 3 different formats: 30 cells and 36 rows, 24 cells and 22 rows, 24 cells and 3 rows, equipped with a frame that serves as a guide to move the ruler and hold the paper securely fixed, it is written with a stylus and erased with the same from the grip side. ## 29) What are the characteristics of the ruler and the cell for Braille writing? The ruler has two rows of cells, in each cell of dimensions (7x4 mm) up to 6 dots can be inserted, each character occupies a cell, it is written with a stylus from right to left but it is read from left to right. ## 30) How is the cell for Braille writing divided? It can contain 6 dots which are arranged in 2 columns and 3 rows. ## 31) How many combinations can be obtained with Braille writing with 6 dots? 63 different combinations, 64 if you also consider the blank space. ## 32) How are the dots conventionally numbered within the cell (Braille)? In reading 1st-2nd-3rd column from left to right from top to bottom; 4th-5th-6th column from right to left from top to bottom; In writing 1st-2nd-3rd column from right to left from top to bottom; 4th-5th-6th column from left to right from top to bottom. ## 33) How are the 63 signs organized in the Braille code? In 5 series of 10 signs each, plus 13 free signs; 1st series includes letters from a to j, 2nd series letters from k to t) is obtained by adding the 3rd dot of the cell to the signs of the 1st series, the 3rd series is obtained by adding the 3rd and 6th dots of the cell to the signs of the 1st series, the 4th series is obtained by adding the 6th dot of the cell to the signs of the 1st series, the 5th series repeats the signs of the 1st series shifted to the bottom of the box. ## 34) What are the disadvantages of the Braille tablet? Writing characters are reversed with respect to reading, ability and training, poor management of corrections and the difficulty of reproducing very voluminous texts. ## 35) What is the purpose of the Braille printer? To print in Braille through a PC using conversion software, it can be single-sided (prints on one side of the sheet) or interpoint (prints front back), there are Braille printers that reproduce both Braille and black and white printing at the same time, so that it is possible to print sheets for both those who see and those who do not. ## 36) What is the Braille dattilo? It is a machine that allows the use of 6 keys plus space, line break and carriage return, for a total of 9 keys, the combination of keys for each character must be pressed simultaneously, the writing takes place from left to right and the characters are immediately legible. ## 37) Can the PC be used for Braille writing? Yes, through the Braille bar or display, which writes in Braille the text elements selected on the PC screen. It is a series of needles arranged in two rows that go up and down; the bar is an output device if it displays in Braille what is selected on the screen, an input device if it writes in Braille on the bar and the text appears on the PC monitor in text format. ## 38) How are the first generation readers constituted? They have a scanner case (see maestro plus) that performs reading through speech synthesis, it can be operated through both voice and manual commands. ## 39) How are the second generation readers constituted? A base, an arm and a camera, more versatile, practical and manageable, voice and manual commands. ## 40) How did Braille code originate? It originated from the evolution of a military code invented by Charles Barbier de La Serre and perfected by Louis Braille, officially adopted in France in 1854, it was extended to other European languages only subsequently thanks to the transcription of the Our Father into 6 languages. ## 41) Were there problems in using it for extra-European languages? Yes, since sounds and letters did not match. ## 42) What is the Braille code composed of? Of 4 elements: dots, cells, rows, Braille tablet- Braille dattilo and Braille printer. ## 43) How are numbers written in Braille? You need to prefix the number with the NUMBER SIGN dots (3-4-5-6) and then write the 1st series of Braille from a to j to describe the numbers from 1 to 9 and then 0. ## 44) How are capital letters written in Braille? You need to prefix the letter with the CAPITAL SIGN dots (4-6). ## 45) What is the key combination to close an active window on the PC? ALT+F4.