1. The SDN iPhone App is back and free through November! Get it today and please post a review on the App Store!
    Dismiss Notice
  2. Dismiss Notice

Physiological Optics Question--darn math.

Discussion in 'Optometry' started by Eyegirl2k7, Apr 11, 2004.

  1. Eyegirl2k7

    Eyegirl2k7 Bridget Jones here
    7+ Year Member

    Joined:
    Nov 23, 2002
    Messages:
    376
    Likes Received:
    0
    Hi all,
    I have an optics question from an assignment I'm doing. Rpames, if you're out there...you know what i'm talking about (Lecture 10-19 review).

    The question is:
    What is the depth of focus in diopters for an eye that perceives a clear retinal image for objects placed between 30-40 cm in front of the eye?

    Since the clarity of image is between 30-40 cm, I converted that to diopters and said that the image is clear between -3.33 D and -2.50 D. Is it more complicated than that? Somehow i feel like it should b e.

    Many thanks,
    Eyegirl
    :confused:
     
  2. Note: SDN Members do not see this ad.

  3. cpw

    cpw It's a boy !!!
    Moderator Emeritus 10+ Year Member

    Joined:
    Apr 25, 2001
    Messages:
    13,393
    Likes Received:
    0
    Status:
    Optometrist
    unless i remember incorrectly i do believe that's all you have to do... but it has been two years.. somebody back me up here :)

    good to see you again eyegirl ;)
     
  4. Andrew_Doan

    Andrew_Doan Doc, Author, Entrepreneur
    Physician Moderator Emeritus Lifetime Donor Classifieds Approved 15+ Year Member

    Joined:
    Oct 1, 2002
    Messages:
    5,633
    Likes Received:
    17
    Status:
    Attending Physician
    You got it. The eye is able to focus the object between -3.33 D and -2.50 D.

    If they had added in a refractive error, i.e. -5.00 or + 5.00, and the accomodation of the eye then you could calculate the near and far points of the eye. In this case, it appears to be an emmetropic eye focusing on an object at 30 cm = 3.33 D and 40 cm = 2.50 D.
     
  5. Eyegirl2k7

    Eyegirl2k7 Bridget Jones here
    7+ Year Member

    Joined:
    Nov 23, 2002
    Messages:
    376
    Likes Received:
    0
    Thanks, faithful SDNers!

    I do not :love: optics.

    Eyegirl
     

Share This Page