Essilor
Setting Up Essilor Designs
Essilor designs differ from most other vendors in a couple of ways.
First, Essilor selects the donor blank in most cases, and returns the OPC of the blanks to use for a job in the LMS file. This means the design must be set up to indicate that the LDS vendor will do blank selection. This is done by checking the appropriate option on the Digital tab of the lens design setup:
This will disable blank selection in Rx-Universe (Rx-Universe will not even attempt to select donor blanks), including base curve selection. If a particular base curve is desired for a job, this can be entered in the "Base curve" field under Lens Selection; for example, to request a 750-base lens, the entry would be as follows:
Freeblank Designs
Essilor has some designs that allow the lab to select the donor blanks to use, and send the technical data of the blanks to DEO, similar to how other LDS vendors allow almost any donor blank to be used.
These designs are known as "Freeblank" designs in Essilor terminology, and need to be explicitly identified in Rx-Universe by sending "__FREEBLANK=1" in the LDS request to DEO. This is done by setting up a VCA over-ride label on the design:
In addition to the __FREEBLANK entry (note that this is TWO underscore characters followed by FREEBLANK), the lens design must be set up to allow Rx-Universe to do blank selection, including setting up a base curve chart for selection. There are no "suggested" base curve charts from Essilor for Freeblank designs, so the lab is free to use any chart desired. There is a "generic" digital selection chart (84) which the lab may choose to try out. If using this chart, the option "Add add to sphere" should be checked, and the option "LDS selects blanks to use" should NOT be checked. An alias entry will also be required to identify the blanks that should be selected for the freeblank design.
LNAM codes for Essilor
LNAM codes for Essilor designs (freeblank or otherwise) are 6 character codes that identify the design, the material, the color and the coating. Therefore, the LNAM is not set in the lens style itself (since it is different based on material, color and coating), but rather is set in a VCA label table. There are two "standard" Essilor tables maintained for Rx-Universe - table "ESS" for Essilor designs in North America, and table "ESSL" for Essilor designs in Latin America. When setting up the Essilor digital type, the DS record must be set up to reference the appropriate table on the "Other tab": 
The table itself is found under "Devices", "VCA Label Table Settings"; one section looks as follows:
The different combinations of material, design, treatment (coating) and color (tint) have different LNAM values which are sent to DEO.
Switching To Short Corridor Designs
For many designs, Essilor offers the design in regular and short. The LMS is responsible for switching to the short design if the seg height of the order is < X (usually 18mm), and the add power is <= 3.00D. (If the add is > 3.00, the regular design is used regardless of the seg height).
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