Which type of magnifier is designed to reduce accommodation by presenting a beam effectively at infinity?

Which type of magnifier is designed to reduce accommodation by presenting a beam effectively at infinity?

• A. Handheld magnifier
• B. Stand magnifier
• C. Collimating magnifier
• D. Telescopic magnifier

Answer: (C)

Presenting the image at infinity lets the eye relax because it no longer has to change focus to bring a near object into sharp view. A collimating magnifier does this by placing the object at the lens’s focal point, so the light leaving the lens is parallel. That parallel beam corresponds to a virtual image at optical infinity, allowing the eye to focus with minimal accommodation while still perceiving a magnified image. Handheld and stand magnifiers are designed to create a magnified image at a near distance, so the eye must accommodate to view it comfortably. A telescopic magnifier uses telescope optics and bets on distance viewing rather than creating an infinity image for near tasks. Hence, the collimating magnifier is the one that reduces accommodation by presenting a beam effectively at infinity.

Presenting the image at infinity lets the eye relax because it no longer has to change focus to bring a near object into sharp view. A collimating magnifier does this by placing the object at the lens’s focal point, so the light leaving the lens is parallel. That parallel beam corresponds to a virtual image at optical infinity, allowing the eye to focus with minimal accommodation while still perceiving a magnified image.

Handheld and stand magnifiers are designed to create a magnified image at a near distance, so the eye must accommodate to view it comfortably. A telescopic magnifier uses telescope optics and bets on distance viewing rather than creating an infinity image for near tasks. Hence, the collimating magnifier is the one that reduces accommodation by presenting a beam effectively at infinity.