HAL PROGRAM

When Windows starts up, Hal takes over the user's communication with the computer environment, announcing not only keystrokes or characters on the screen but also objects in the Windows environment, giving a complete picture of menus, dialogs and icons and generally the status on the computer screen.

Hal is the basic tool of every blind computer user, since with the help of the voice synthesis program it contains, it achieves the reading of the screen data through the sound card and the speakers of our computer.

Hal's simultaneous Braille display support also gives visually impaired people tactile access to information.

Significant capabilities

• An access software that supports simultaneous reading and rendering in Braille format of computer screen data, fully meeting the needs of people with vision loss.
• Greek environment with full Greek and English support.
• Screen reader, speaks any text that appears on the screen (documents, menus, web pages, emails, etc.) as well as the icons and some of the graphic elements, announcing vocally all the Windows environment objects that appear on the screen computer.
• Hal works with all popular screen reader speech synthesis software. The sound card of the computer is used for pronunciation (no additional pronunciation device is needed). In particular, for the pronunciation of Greek and English with higher voice synthesis quality than that available with Hal, we use the PhonAesthesia voice synthesis software.
• Support for all known Braille displays.
• Ability to install on more than one workstation by purchasing additional licenses.
• Freedom to use the software on any computer using the Dolphin Pen without the need for installations or CDs. Useful for students or workers who need to work on multiple workstations.

What is the BRAILLE system?
Braille is a tactile reading and writing system. It consists of raised dots that replace the letters of the alphabet and is named after a blind Frenchman, Louis Braille, who invented it. Its basis is the "hexastigmo": six embossed dots, placed three by two in two columns, like the six on a die. For easier identification the dots are numbered from top to bottom 1-2-3 left and 4-5-6 right.
1 · · 4
2 · · 5
3 · · 6
63 combinations can be formed with these six dots.
Braille is read from left to right and top to bottom, just like common sighted writing. To learn to read with the hands, it takes a lot of practice to get the right movement of the hands and fingers and especially to develop the sense of touch

Perceptual processes
Braille readers and sighted readers are primarily language users, using similar processes to make sense of a text (Danielson et Lamb, 1983). The reader who reads by touch moves his finger over the line of raised dots, from left to right, as a sighted reader moves visually (with his eyes) over the form; and the braille lines are read from the top of the page down, as is done with printed text (Challman, 1996; Gale & Cronin, 1990).
The sighted reader takes in one word or set of words at a time and then proceeds gradually through his text, at a speed that depends on experience, eye adaptation, concentration, etc.
The braille reader unscrambles his text by moving from one character/letter to the next within a word, holding the characters in memory to make words and phrases (Lamb, 1996).
The perceptual processes for viewers are well known (Smith, 1986). Regarding braille reading, research has been done on how braille characters and words are perceived (Barraga, 1983; Kederis, 1963; Lewi-Dumont, 1997).
By looking at the perceptual processes involved in the mechanism of reading, we can point out several differences between sighted and blind readers: Despite the similarities between visual and tactile learning and the way sighted and blind children are trained, blind children do not they can learn by imitation what they see. They have limited experiences, fewer opportunities than viewers to acquire situational knowledge, as well as limited access to appropriate (relevant) reading material (Danielson & Lamb, 1983; Lederman, 1982).

Memory processes
In considering the role of memory in the braille reading process, it should be considered: a) sensory records b) proximal memory c) that braille readers additionally need to develop tactile memory (Millar, 1974) and will also the following factors must also be considered (Knowlton & Wetzel, 1996):
a. The reader may become so engaged in the tactile process that they pay no attention to the further processing of the information.
b. The perceptual process may be so slow that the retention of information in memory is hindered or disrupted.
c. The perceptual "window" for braille is small, especially for one-handed readers.
d. Sustaining attention in the form of repetition or different modes of processing is necessary for information to be retained in short-term memory and then transferred to long-term memory.