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Ms. Wendy Nichols - COMS ( Certified Orientation and Mobility
c/o Betacom Corporation Inc.
800-353-1107 ext. 230
History - Telescope Use within Orientation and Mobility Training Programs
The VVT300(tm) - Features that support vision enhancement training and mobility
Goal Setting via Assessment
Training with the VVT300(tm)(tm):
Training Activities with the VVT300(tm)
3) Near Tasks
Prior to training students in the use of the telescope, it is important that you first become familiar with the device. Learning to locate the controls, how they operate, and the features available, will assist you in portraying the benefits of the VVT300(tm) to end-users.
If the student has had prior experience with CCTVs and/or telescopes, the VVT300(tm) can be compared to these devices, and the same training principles applied to training with the VVT300(tm).
Familiarity with localizing, spotting, tracing, tracking, and scanning, as well as eccentric viewing techniques for students with scotomas, will require review prior to training with the VVT300(tm). As with all vision training, you will need a variety of materials of varying size and colour contrast, allowing for the goals that have been identified by the student.
A verbal review of training principles should be undertaken prior to using the telescope, to refresh the students memory with regard to localizing, fixating, focusing, tracing, tracking, and scanning. Success is found with distance activities in the beginning of training.
Once the target is located visually without the telescope, the student can hold the telescope up to the preferred eye and begin to zoom in on the target object. The closer the aid is held to the eye (or glasses) the larger the field of view on the personal, high resolutions screen will be.
During this initial training, students should be encouraged to use the minimum amount of magnification through the telescope, thereby providing a larger field of view. After viewing each target, it is recommended that the student zoom out before locating another target object to view.
Once a target is located through the telescope, fine focusing is available with the use of the white 'freeze' button under the ocular lens. With the image captured on the screen, fine focusing occurs by turning the eyepiece clock-wise three (3) times ONLY, or counter-clockwise three (3) times ONLY. The image can then be changed from colour to reverse, with the horizontal button in the middle of the controls. This serves to provide better contrast for the viewer by eliminating colour. Additionally, the CONTRAST INCREASE or CONTRAST DECREASE buttons located near the objective lens on the top of the telescope will allow the student to change the light and dark areas of an image to increase the contrast within the image itself.
Due to the automatic focus feature within the VVT300(tm), it is not necessary to focus the device manually (unless the fine focus feature is examined while the image is captured).
The VVT300(tm) will focus on a target object if it is in the objective lens of the telescope. Starting at the lowest power (1/2X) the student should zoom in slowly on the target object (ie. the wall clock or poster at 3 m) until that target object fills the screen.
Students can gain experience with the auto-focus mechanism by looking at a distant object (ie. the clock) and then focusing on another target (ie. the instructors face) at a closer (mid-range) distance. This will serve to demonstrate the focusing ability of the camera, and the response time, as well as localization skills.
Tracing involves following a stationary line in the environment. This skill is especially important for mobility purposes, as it can be used to visually locate the blackboard at the front of the classroom, the baseboard along the hallway, the grass shoreline bordering the sidewalk, crosswalk lines on the road, poles holding traffic signage, storefronts in a mall or along a street, or grocery items on a shelf.
Lines to trace may be made with black tape on a white wall, black marker on a white board, or chalk on a blackboard. Initial trials should involve horizontal or vertical lines, and then progress to diagonal or curved lines, then geometric shapes.
Once the student becomes proficient at tracing, the numbers or letters can be replaced by words or phrases, and the size and contrast decreased progressing to curved lines (solid, broken, dashed, dotted) of varying colours, with numbers interspersed beside them, will assist the instructor in identifying the accuracy of the students tracing ability.
The auto-focus feature of the telescope is especially helpful here, as it will focus on the target immediately, regardless of the distance from the student, once the target is within the viewing screen of the telescope. Using minimum magnification levels will greatly assist in orientation, with zooming in for detail as required.
In the training room, it is helpful to amass a variety of signs and materials which will be meaningful to the students. Geometric shapes of various colours, high contrast numbers and letters of varying sizes, street signs, stop signs, traffic lights, house numbers, and a wide variety of other signs and symbols will be useful here.
Kitchen clocks of varying colours can be placed on the wall to demonstrate the use of magnification and contrast with the VVT300(tm). The black clock on a white wall will show up easily, but so will a lighter coloured one with the contrast increase button and/or the reverse image button activated.
Posters with minimal visual clutter, large wall maps, and Snellen charts will provide a good basic introduction to the workings of the VVT300(tm).
These activities can be incorporated as reinforcements to the classroom curriculum for activities in Mathematics, English, and Science classes. Following students in the school yard, watching the sports activities in Phys. Ed. Class, checking the faces of classmates or teachers for expression or demonstration, watching the school buses pull into the driveway, and checking the hallways for friends are skills that students generally enjoy learning and practicing a great deal. Reading homework off the blackboard independently is not always a favourite activity, but is quite useful and necessary for most students.
Once these skills are mastered indoors, the student can be given the opportunity to practice these skills outdoors, locating street signs, traffic lights, stop signs, store signs (on the same side of the street and across the street), house and building numbers, and overhead signage in grocery stores or other public buildings.
Tracking moving objects is more difficult, but with sequential training and experience, students can become very adept at this skill. Following their friends in the school yard, tracking people moving down the sidewalk or in the mall, watching sports games in the gym or outdoors, are some fun activities which will develop tracking skills.
Identification of faces is a very practical mid-range activity with the VVT300(tm). The student can scan a row of faces (or pictures) to identify a particular one, zooming in or out as necessary, and utilizing the contrast increase or decrease buttons as needed. The reverse image feature is often helpful for identifying faces, although many people find that the image does not look 'real' enough when reversed.
Other mid-range activities, many of which are included as a
component of the educational curriculum are:
letter/number/pattern recognition on a chalkboard or white board
watching in-class demonstrations
checking science experiments
Many people place reading again at the top of their wish lists. Although the VVT300(tm) with the reading cap does make spot reading possible, it is not generally feasible for sustained reading activities. The development of a docking station for the VVT300(tm) will allow the unit to act like a CCTV system, when used in conjunction with a television monitor. This system will be much more comfortable for sustained reading and writing activities, and will be available in the near future.
If reading is attempted, it is more successful when the material is of high contrast, on non-glare paper, and is placed on a reading stand so as to accommodate the angle of view with the telescope. The use of a typoscope or coloured acetate paper as line markers have been found to be beneficial for persons who are learning to read using magnification aids.
Some additional training activities at near using the
reading mail to identify the sender
looking up telephone numbers
The use of a felt tip pen and bold lined paper will make it easier for students to locate their pen tip, and their place on the line, with the VVT. The student should first locate the upper left corner of the page with the telescope, then slowly bring the pen tip up towards the corner until it is visible in the VVT screen prior to commencing writing. A left to right pattern is preferable, with the student tracing back along the line just written, then dropping down a line to resume writing.
Sequencing is critical to success. Beginning indoors, seated, with large, high contrast targets will give your students the skills and confidence they need to head outdoors with the VVT.
As success is demonstrated, decrease the size, then the contrast, of your targets. Lastly, adding background clutter will enable students to identify their targets readily and comfortably in real-life situations, with ease and accuracy, practice and patience.
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