Overview:

Wrap frames provide an additional challenge to an optical laboratory over more traditional prescriptions. The tilt (both Panoramic and Pantoscopic) associated with a wrap frame cause a change to the prescribed power of a lens, which can be compensated for in the laboratory in order to minimize unwanted optical effects to the patient.

Rx-Universe is pleased to offer a tight integration with KBCO’s AccuCalc compensation for wrap frames, using the KBCO SV Wrap and EOS Wrap lenses. This document outlines how to trigger Rx-Universe to use the KBCO AccuCalc calculations for a given Rx.

NOTE: At present, wrap compensation is done only for KBCO lenses. Formulae for compensation of other lenses may follow in future versions of Rx-Universe.

In addition to calculations done for traditional jobs, the wrap parameters may also be used for digital lenses, such as digital near vision and digital as-worn designs. Your digital vendor can advise which lens styles should be set up to allow wrap parameters to be specified for them.

Specifying System-Wide Defaults

There are four parameters used for wrap calculations. The default values for these are specified on the “Surf1” tab in System Parameters (values shown are typical defaults):

Specifying Wrap Frame in a Manually-Entered Order:

When entering an order, click on the “F12/Opt” button (or just press the “F12” key):

To indicate that you want wrap calculation just click on the “Wrap” radio button to insert a checkmark.

The values shown here are default parameters, as set by the lab on the System Parameters screen (explained above). All of these parameters can be specified by the dispenser, and the two angles can be specified on a particular frame trace.

Pantoscopic Angle	:	Tilt along the horizontal axis
Panoramic (Wrap) Angle	:	Also known as faceform angle or tilt along the vertical axis, the amount of wrap
Vertex Fitting Distance	:	Back vertex distance with frame fitted
Vertex Refracting Distance	:	Back vertex distance used for refraction

The “Use Shamir Panorameter” flag allows the user to enter wrap values from the Shamir Panorameter device – these values are measured differently than traditional wrap angles and must be in the range 70 to 130. Whether this checkbox is active for a job is determined by the Lens Style – the Lens Style must be set up specifically to allow Shamir Panorameter values to be used.

The “Defaults” button restores all fields to the default values from the System Parameters and/or the angles from the Pattern database (if applicable on the order).

Triggering Wrap Values by Lens Style

Some Lens Styles imply that wrap parameters should be entered for a job – these include specific wrap designs (KBCO EOS Progressive Wrap, for example), and digital designs which require wrap parameters (digital as-worn designs, for example). Rx-Universe provides support for Shamir Panorameter values as well – these values should be used only for Shamir digital designs (such as Shamir Attitude lenses).

On the Lens Style General tab, two checkboxes may be set:

Checking “Do Wrap Calcs” allows wrap values to be specified on an order using this lens style.

Checking “Allow Shamir Panorameter” allows the Shamir Panorameter checkbox on orders using this lens style.

Manual Order - Example:

The following KBCO EOS Wrap Rx was entered manually, with default values for tilts and vertex distances:

In order to obtain the desired power in a wrap frame, what is actually ground into the lens must be modified. When calculations are done, the sphere and cylinder Rx is adjusted so that the desired power will be obtained when the lens is mounted in the frame. For this reason, “compensated” values are printed on the work ticket, as follows:

The central part of the work ticket shows the tilt and vertex distance parameters used for the calculation; the tilt is shown as Pantoscopic tilt/faceform tilt, and the vertex distance is shown as fitting/refracted.

The modified sphere and cylinder powers are used to calculated curves for grinding, and prism is induced to compensate for the tilt of the lens in the frame. When the lens is checked at QA, it should be checked for the “compensated” power, not the prescribed power. As KBCO describes in their manual:

Rx Dr. Prescribes = Rx Patient Sees Rx Lab Produces = Rx Lensometer Reads

Specifying Wrap Compensation on the Invoice:

To assist the dispenser in correctly checking the lens for power, the invoice will include a line for each eye, in the comments, showing the wrap compensation. These compensated values are what the dispenser should check in their lensometer (see above section). For example, on the PCL invoice format, the following would show in the Special Instructions section:

This shows the dispenser what to check for in the lensometer. In the example above, the information shown (for the right eye) is:

+6.06	:	Sphere Power
-1.03@117	:	Cylinder Power and Direction
0.32I	:	Prism 0.32 Base In
0.43U	:	Prism 0.43 Base Up

Specifying Frame Angles on a Trace

The panoramic (wrap) angle and pantoscoptic angle can each be specified on a particular trace. The wrap angle is the same as the ZTILT field:

If there is a different ZTILT for the left eye than for the right eye, the different values WILL be sent to a device requesting ZTILT.

Under the “Devices” tab, the Pantoscoptic tilt can also be specified for a trace:

Specifying Wrap Frame in an Electronic Order (GIF format):

For electronic orders coming from a third party, five new labels have been added to the original OMICS electronic GIF specification to handle wrap frame calculations, as follows:

WRAP 1 byte, Y or N – if set to Y, triggers wrap calculations.

If other parameters are not given, default values (as described earlier) are used

FACEFORM-TILT Numeric, format 99.9, range +5.0 to +30.0

Numeric, format 999, if within range 70 to 130, triggers Shamir Panorameter

PANTO-TILT Numeric, format 99.9, range +5.0 to +30.0

VERT-FITTING Numeric, format 99.9, range +5.0 to +20.0

VERT-REFRACT Numeric, format 99.9, range +5.0 to +20.0

Specifying Wrap Frame in an Electronic Order (VCA format):

For electronic orders coming from a third party, five new labels have been added to the OMICS interpretation of the electronic VCA specification to handle wrap frame calculations, as follows:

_WRAP 1 byte, Y or N – if set to Y, triggers wrap calculations.

If other parameters are not given, default values (as described earlier) are used

ZTILT Numeric, format 99.9, range +5.0 to +30.0