| Device
|
Description
|
Advantages
|
Disadvantages
|
| Hand-held magnifier |
"Sherlock Holmes" type portable magnifying glass. |
Small and inexpensive. Available in a wide range of powers (1.5X - 8X). Socially-accepted. |
Leaves only one hand free. Difficult to keep in focus if hand trembles. Clamps with flexible arms are available for attaching to table tops. |
| Illuminated hand-held magnifier |
Portable lens with handle and built-in battery-operated light. |
Small and inexpensive. Available in a wide range of powers (1.5X - 8X). Socially-accepted. Useful for dim subject areas. |
Leaves only one hand free. Difficult to keep in focus if hand trembles. Clamps with flexible arms are available for attaching to table tops. |
| Stand magnifier |
Magnifier on a stand with built-in legs for table tops or books. |
Maintains steady focal distance. Comes in a wide range of powers (1.7X - 8X). Possible to write beneath and use both hands. |
Bulkier than hand-held device. Sometimes difficult to get sufficient light between the lens and the subject. |
| Hand/Stand magnifier |
Combination of hand-held and stand magnifier. |
Can be used as either by folding handle and legs, so more portable than a regular stand magnifier. Comes in powers of 2.5X - 3X). |
None. |
| Illuminated stand magnifier |
Illuminated magnifier on a stand with built-in legs for table tops or books. Light source is either a built-in battery-operated bulb, a halogen lamp (A/C), or the more superior LED illumination (D/C). |
Provides shadowless light close to the subject. Maintains steady focal distance. Comes in a wide range of powers (1.7X - 8X). |
Difficult to write beneath most models. Even more bulky than an ordinary stand magnifier. Battery-operated models (except LED version) can be expensive to run. |
| Illuminated bench magnifier |
Same as above, but mounted on an adjustable arm mounted to a table top or work bench. |
Good for using both hands for sewing, hobbies, etc. |
Limited magnification (rarely above 3X). Comparatively expensive. |
| Dome/Bright Field magnifier |
Half-spherical magnifier (like a paper weight) that rests directly on the page. Largest dome available is 90mm. |
Always in focus. Distributes light well onto the surface. |
Made of heavy glass, rather than plastic. |
| Bar magnifier |
Semi-cylendrical lens which rests directly on the page, magnifying one line of print at a time. |
Makes tracking of a line of text easier. |
Limited level of magnification power (up to 3X). Reflected light and distortion can be problematic. |
| Spectacle-mounted magnifier |
Magnification lenses mounted on spectacles. |
Leaves both hands free. |
Short working distance, due to limited level of magnification power of up to 3X. Single magnifying lenses (for one eye only) are available from 4X to 12X. |
| Clip-on magnifier |
Magnifying lens which attaches to regular spectacles. Binocular versions available in powers 2X - 4X. Monocular versions available up to 7X. |
Leaves both hands free. |
Short working distance, due to limited level of magnification power. |
| Hand-held or spectacle-mounted telescope |
Telescopes of low magnification (up to 4X), which can be mounted on spectacles for near intermediate and distance viewing. |
Good for reading music, viewing TV or plays, reading signs, etc. |
Restricted field of view. Best for stationary viewing. Focus is fixed, except for the more expensive "Ocutech" model, which mounts on spectacles and features an auto-focus capability. |
| Field expanders/minifiers |
Lenses which reduce the apparent size of the subject (like a "peephole" in a door). |
Useful for people with good central vision, but diminished peripheral vision. |
None. |
| Closed circuit television (CCTV)/Video magnifier |
Device utilizing a camera and monitor to magnify a page or object. The display can be monochrome or full color, and the products are available in a variety of screen sizes and magnification levels. Some models are designed for interconnection with computers. All models allow adjusting contrast and reversing black and white. |
Books and objects can be placed beneath the camera for viewing. Sufficient room to write. |
Comparatively expensive. Not portable. |
| Portable closed circuit television (CCTV)/Video magnifier |
Portable magnifying device utilizing a camera approximately the size of a computer mouse, plus an interface for connecting to a standard television or head-mounted display. Most models allow changes in magnification, adjusting contrast and reversing black and white. |
Can be carried in a purse or backpack. Battery power option. Less expensive than stationary CCTV models. |
Some practice required for smooth operation of the hand-held camera. One-handed operation. Cannot be used for magnification of writing or hand work. |
| Portable video magnifier |
Portable magnifying device with a self-contained camera and viewing screen. Some models allow freeze-framing. Most models allow changes in magnification, adjusting contrast and reversing black and white. |
Can be carried in a purse or backpack, or in its own carrying case. Battery power option. Less expensive than stationary CCTV models, but more expensive than a portable CCTV without a viewing screen. Useful for reading labels or menus, writing checks, and performing other close-up tasks not requiring a wide field of view. |
Field of view is too small for reading books. |