OBM: The concept behind the revolution
On-Block Manufacturing (OBM) is a new streamlined method for producing completed prescription eyeglass lenses in a very short period of time – using one block to create an integrated production line.
The method involves blocking a semi-finished lens blank onto a unique plastic machineable surfacing block and then keeping the blank on the same block all the way through coating and even up to finishing.
Using the Satisloh Nucleo blocking system as a “process integration platform” also allows a lab to combine two or even three departments (surfacing, coating, and optional finishing) into one integrated production line using either a manual line version or completely automated line system.
the production process could even be fully automated without any operator ever touching the lenses
The new method eliminates about 70 per cent of the normal labour required to produce a prescription lens and with further improved yields, the cost to manufacture customised eyeglass prescriptions can be greatly reduced.
In high volume labs, the production process could even be fully automated without any operator ever touching the lenses.
In addition, the complete job with high quality anti-reflection (AR) coatings is produced in less than two hours, which provides a lab with a new way to differentiate itself from near-shore or offshore competition, with their typical turnaround time of up to 10 days for getting consumers’ prescriptions back from a lab.
Why is OBM now possible?
In many cases, lab owners want to know why this production method is suddenly now possible when glasses have been made basically the same way for more than 80 years. There are two reasons.
First, new plastics and UV cured adhesive technology are allowing lens blanks to be blocked on a machineable block for the first time.
The Nucleo plastic block material is inexpensive, but rigid enough to hold a lens firmly with full surface support through all production steps. It is also non-porous enough so that it does not hold water and can, therefore, be AR coated in a vacuum chamber with only minimal degassing times.
The second and more important reason that OBM has become a reality is due to the introduction of FBS (Full Back Side) digital surfacing technology, also referred to as free form technology, which now allows the entire prescription to be cut onto the back of a lens.
Smaller Inventory
With the advent of Full Back Side progressive designs, a lab can now get by with primarily single vision spherical blanks (five to nine base curves) in a few materials resulting in a need to only carry inventory numbered in dozens of SKUs, as opposed to thousands, making it financially feasible to carry both hard-coated and AR-coated SF (Side Front) lens blanks.
The main concept behind OBM is that local labs, by carrying front side pre-treated blanks, now only need to
process the back side of a lens.
Traditionally, lens treatments AR coating and hard-coating had to be added to the both sides of lenses after cutting the prescription on the back, which required many steps and a lot of handling and process time. So if a lab wanted to offer AR coated lenses, hard-coated lenses, polarised lenses, and photochromic lenses in multiple materials and designs, the inventory requirements were enormous. It was financially impractical to carry all of their lens blanks front side pre-treated with more than one or two of those treatments.
Instead it was cheaper to carry un-treated blanks and then treat both sides after the prescription was cut into the lens. Now, however, since there is only a need to carry single vision spherical blanks in a few base curves in each material, it is easily financially justified to carry front side pre-treated blank inventories for each lens treatment.
Contact Details
Australian Representative
9 Bracken Court
Cashmire Qld 4533
Contact: Mostyn Whitehouse
T 07 3298 5575
F 07 3298 5545
W www.satisloh.com
E [email protected]
