Results 1 to 7 of 7

Thread: Help figuring this one out!

  1. #1
    Rising Star
    Join Date
    Jan 2006
    Location
    Florida
    Occupation
    Dispensing Optician
    Posts
    87

    Help figuring this one out!

    A guy needs a glass lens 75mm diameter lens + or - with a focal distance of 200mm to heat water with the sun! I am not sure of the application? What lens? I'm thinking a 75mm +4.50

  2. #2
    Banned
    Join Date
    Jun 2000
    Location
    Only City in the World built over a Volcano
    Occupation
    Dispensing Optician
    Posts
    12,996
    I think a lens of +5.00 would come closer to a 200mm focal length.

  3. #3
    ABOM Wes's Avatar
    Join Date
    Nov 2007
    Location
    Earth
    Occupation
    Optical Laboratory Technician
    Posts
    3,194
    Quote Originally Posted by chip anderson View Post
    I think a lens of +5.00 would come closer to a 200mm focal length.
    +1
    Wesley S. Scott, MBA, MIS, ABOM, NCLE-AC, LDO - SC & GA

    “As our circle of knowledge expands, so does the circumference of darkness surrounding it.” -Albert Einstein

  4. #4
    Rising Star
    Join Date
    Jan 2006
    Location
    Florida
    Occupation
    Dispensing Optician
    Posts
    87
    Where do you get a plus 1

  5. #5
    Master OptiBoarder optical24/7's Avatar
    Join Date
    May 2006
    Location
    Down on the Farm
    Occupation
    Dispensing Optician
    Posts
    5,830
    Cat, Wes is agreeing with Chip. (As I do, a +5.00 has a focal length of 200mm.)

  6. #6
    Doh! braheem24's Avatar
    Join Date
    Feb 2001
    Location
    KOCF & 89ft ASL
    Occupation
    Other Eyecare-Related Field
    Posts
    3,843
    Making one of these?

  7. #7
    Manuf. Lens Surface Treatments
    Join Date
    Aug 2002
    Location
    in Naples FL for the Winter months
    Occupation
    Other Optical Manufacturer or Vendor
    Posts
    23,240
    Integrative Pressurized Solar Water Heater-HP........a little more expensive than a lens but more effective

    http://honger88.en.made-in-china.com...Heater-HP.html

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Formula for figuring out Dynamic plud Diopter power??
    By Tpopticians in forum Ophthalmic Optics
    Replies: 1
    Last Post: 05-21-2009, 01:22 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •