![](https://optoplus.cloud/wp-content/uploads/2024/01/starterplus-1.png)
![](https://optoplus.cloud/wp-content/uploads/2024/01/Asset-175.png)
The Best Opto+ entry level soft progressive design
BASIC PLUS - STARTER
Different corridor lenghts for various wearer’s habit
Description & details
BASIC PLUS - a multipurpose optimized design
![](https://optoplus.cloud/wp-content/uploads/2024/01/basicplus-s-c.jpg)
![](https://optoplus.cloud/wp-content/uploads/2015/09/Asset-9.png)
Opto+ design Specification
![](https://optoplus.cloud/wp-content/uploads/2015/09/Asset-8.png)
- The corridor length calculation starts from the geometrical lens center or the Prism Reference Point (PRP) to the beginning of the Near Reference Point (NRP)
- The Fitting Cross (FC) is set at +4mm from the Prism Reference Point (PRP)
- The Distance Reference Point (DRP) is set at +4mm from the fitting cross
- The Near Reference Point (NRP) is set a -4 mm from the end of the corridor
- The INSET is the distance between the hypothetical vertical line passing through the Fitting Cross (FC) and the hypothetical vertical line passing through the Near Reference Point (NRP)