Why can't someone who is myopic see reflections clearly?

  • Context: High School 
  • Thread starter Thread starter joriarty
  • Start date Start date
Click For Summary

Discussion Overview

The discussion revolves around the phenomenon of myopia and its effect on the clarity of reflections in mirrors. Participants explore the reasons why individuals with myopia, or short-sightedness, experience blurriness when viewing reflections of distant objects, even when they can focus on the mirror's surface itself. The scope includes conceptual understanding of optics and vision correction.

Discussion Character

  • Conceptual clarification, Technical explanation, Debate/contested

Main Points Raised

  • One participant notes that when myopic individuals remove their glasses, distant objects remain blurry, and this includes reflections in mirrors, as the mirror does not correct myopia.
  • Another participant explains that images in a mirror are not located in the plane of the mirror but rather behind it, at the same distance from the mirror as the actual objects in front of it.
  • A later reply expresses gratitude for the clarification but also indicates a struggle with retaining foundational physics concepts amidst more complex studies.

Areas of Agreement / Disagreement

Participants generally agree on the mechanics of how reflections work in relation to myopia, but there is no explicit consensus on the broader implications or the participant's understanding of foundational concepts.

Contextual Notes

Some assumptions about the nature of light paths and the perception of images in mirrors may not be fully articulated, and the discussion does not resolve the complexities of myopia's effects on vision.

joriarty
Messages
61
Reaction score
0
I have always wondered about this - I have moderate short-sightedness (5 diopters). If I take off my glasses and stand close enough to a mirror that I can focus sharply on the actual surface of the mirror (or the wall behind it), the reflections in the mirror of more distant objects are still just as blurry as if I were looking at those objects directly.

Does anyone know why this is?
 
Science news on Phys.org
If you are myopic and take off your glasses, distant objects will be blurry. Looking into a mirror does not correct your myopia, so distant (reflected) objects will still be blurry. This is why Optometrists use front-surface-silvered mirrors to extend the light paths in their examination lanes.
 
joriarty said:
If I take off my glasses and stand close enough to a mirror that I can focus sharply on the actual surface of the mirror (or the wall behind it), the reflections in the mirror of more distant objects are still just as blurry as if I were looking at those objects directly.

The images are not located in the plane of the mirror. They're located behind the mirror, at the same distance from the mirror plane as the corresponding objects (which are of course in front of the mirror).
 
jtbell said:
The images are not located in the plane of the mirror. They're located behind the mirror, at the same distance from the mirror plane as the corresponding objects (which are of course in front of the mirror).

Ah of course! Thank you. While my studies get increasingly complicated I unfortunately seem to be forgetting the basic foundations of physics...
 

Similar threads

  • · Replies 15 ·
Replies
15
Views
4K
  • · Replies 6 ·
Replies
6
Views
5K
  • · Replies 6 ·
Replies
6
Views
15K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 26 ·
Replies
26
Views
12K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 7 ·
Replies
7
Views
6K
  • · Replies 15 ·
Replies
15
Views
14K