Results 1 to 8 of 8

Thread: Free-form, schmree-form...

  1. #1
    What's up? drk's Avatar
    Join Date
    Mar 2004
    Location
    Ohio
    Occupation
    Optometrist
    Posts
    9,385

    Stick out tongue Free-form, schmree-form...

    If a big part of the success of these free-form individualized progressives depends on my ability to measure pantoscopic tilt angle, amount of downgaze when reading, and vertex distance I AM SUNK! I can't measure that stuff!

    Not to mention the fact that all this technology will instantly go to waste as my poor adjusting skills allow the frames to slide halfway down the patient's nose, or the patient bumps up against the wall and has one temple bent downwards, or heaven-forbid I fit a springy, hingeless titanium rimless frame!

    :hammer:

  2. #2
    OptiBoard Professional Ryan's Avatar
    Join Date
    Jun 2000
    Location
    Hurst , TX
    Posts
    183
    have you ever heard of prozac?:bbg: Have some confidence!!:idea:

  3. #3
    I actually caught a Zeiss rep who had memorized the spiel on this. he said to me that there was a .25 diopter change for every mm of vertex. HA!

    When I asked him at what power is this true? He had no idea.

    DRK, The measurements are really easy. Get the measuring tool from Zeiss, it works although it appears cheesy at first.

    And please don't short change your astigmatics. They will be better off with "standard specs" for measurements, than a standard progressive.

  4. #4
    Master OptiBoarder OptiBoard Gold Supporter Judy Canty's Avatar
    Join Date
    May 2000
    Location
    Virginia Beach, VA
    Occupation
    Dispensing Optician
    Posts
    7,482

    Just when I thought...

    well...anyway. drk, at least half of the success of using any progressive design is in the proper frame selection and adjustments. The rest is directly related to proper measurements. If you don't trust your skills, then hire someone with enough experience to do this for you. Ohio requires that Opticians be licensed and that should be your minimum requirement. Since this person will probably have more interaction with your patients than anyone else, it's the smart and cost efficient move. Having worked with progressive designs of many kinds for more than 30 years, I can say with a modicum of confidence that these new designs are great and perform as advertised. However they're only as good as the Refractionist who wrote the rx and the Optician who filled it.

  5. #5
    What's up? drk's Avatar
    Join Date
    Mar 2004
    Location
    Ohio
    Occupation
    Optometrist
    Posts
    9,385
    Judy, you are a nice lady! I was really kind of tongue-in-cheek with that post. I wonder if the improvements in design are more than just miniscule. If it comes down to things as critical as vertex distance and pantoscopic tilt angle, then that lens seems way to sensitive to be practical! Is that stuff really needed? Does a 12mm vertex distance as measured in our office with the "vertometer" even mean anything when the glasses will slip down to 14 mm when it's hot? Are we being sold a load of ****? I'm a skeptic!

    If, however, the design has less aberration and is therefore more forgiving instead of less, then sign me up!

  6. #6
    I beleve a vertometer is a lensometer, and a distometer measures vertex.

  7. #7
    Master OptiBoarder Darryl Meister's Avatar
    Join Date
    May 2000
    Location
    Kansas City, Kansas, United States
    Occupation
    Lens Manufacturer
    Posts
    3,700
    Keep in mind that as-worn optimization, which is the particular feature you are describing, is only one possible benefit of individualized progressives. And note that small changes from the intended position of wear won't make a huge difference or "negate" the as-worn optimization used for the design.

    The peripheral optical performance of each prescription can also be fine-tuned, which is not possible with a semi-finished lens blank. For instance, the free-form design can incorporate a kind of "atoricity" to improve off-center performance regardless of the sphere or cylinder power. The design can also be compensated for the power errors produced by large amounts of prescribed prism. This all translates to wider fields of vision for most prescriptions.

    Lastly, manufacturers can also create entirely different progressive lens designs for each wearer that have been specifically tailored for factors specific to the individual wearer. In essence, free-form technology allows for an unprecedented level of customization and performance for progressive lens wearers.

    Best regards,
    Darryl

  8. #8
    Master OptiBoarder Joann Raytar's Avatar
    Join Date
    May 2000
    Location
    USA
    Occupation
    Dispensing Optician
    Posts
    4,948
    mrba said:
    I beleve a vertometer is a lensometer, and a distometer measures vertex.
    ... and well fit frames and good lens/Rx match should keep most folks glasses from slipping down when it gets hot.

    You are correct, it isn't a perfect world all of the time but hopefully newer frame and lens materials will help most people.

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Free software for optical industry?
    By deb101 in forum General Optics and Eyecare Discussion Forum
    Replies: 16
    Last Post: 11-01-2007, 11:13 AM
  2. Free Form & Independent Labs
    By johntricity in forum General Optics and Eyecare Discussion Forum
    Replies: 6
    Last Post: 11-22-2003, 09:41 AM
  3. Replies: 0
    Last Post: 03-21-2003, 02:18 PM
  4. Should cross burning be a protected form of free speech?
    By Joann Raytar in forum Just Conversation
    Replies: 27
    Last Post: 12-14-2002, 05:59 PM
  5. FREE STUFF
    By steel in forum Optical Marketplace
    Replies: 0
    Last Post: 08-28-2000, 05:47 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
  •