Concave And Convex Lens

You take the high road and I'll take the shortcut

These fine folk have been collecting the labels in the belief that a certain number would get them a wheelchair.

Well, we heard from plenty of people who are collecting tea-bag labels, but we didn't hear from a single person who could give us the name of a charity involved. And this, says Dave, is because the whole thing is a scam.

`` I suggest that they send them to the recycle tip. Someone has led them up the garden path without the wheelchair I'm afraid.

``These types of scams, as harmless as they are, have been happening for many years, and regardless of how harmless it is, it's still sad that it happens.

``May I also suggest that they collect beer stubby screw caps or wine bottle tops and enjoy the contents. No, you won't get a new wheelchair, but you will sleep better.''

Of course, it's possible that Dave's wrong, so if you know the name of the charity involved, we're still happy to know its name.

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WE received a press release on Thursday and we think it's to promote an exhibition of paintings called aifImpossible Objectsaif, but we're not really sure.

This was part of the opening paragraph.

aif``Impossible Objects extends this spatial investigation by considering gestalt relationships between figure and ground, based on the optical illusion of impossible or undecidable objects.''aif

Confused, we pushed on.

``aifIn Impossible Objects, spatial incongruities are primarily explored through the lens of appropriated imagery.''aif

Buit we couldn't get any further than this bit.

aif``Hinkleys recent object-based works have utilised indentations that move between concave and convex, focusing on the counterplay between mass and space via the trope of obsessive patterning.''aif

We can only hope that the things on display aren't as confusing.

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JOKE of the Week

TWO women find themselves talking to each other at a cocktail party.

``Aren't you wearing your wedding ring on the wrong finger?'' asked one of the women.

``Yes, I am,'' said the other. ``I married the wrong man.''

``Well,'' said the first woman, ``I recently inserted an ad in the classifieds under the heading of `Husband Wanted'. Next day I received a 100 letters. They all said the same thing: `You can have mine'.

Plano Concave Lens | LABEQUIPMENTDISCOUNT.COM

As most designers know, optical design software can be a powerful tool. But it’s just that, a “tool”. The proper interpretation of optimized results is just as important as the input of correct information. That is why experienced designers weigh the advantages and disadvantages of using one lens design code over another prior to any actual design. But with growing industry demands, designers need to incorporate all aspects of production into their design in order to ensure that the final product will be brought successfully to market. Designers need to not only be aware of the nuances of fabrication, assembly, coating, etc, but also with how to integrate costs with the demands of the intended application. Unfortunately, no software provides a subroutine to assure that costs are minimized.

The need to minimize costs is addressed by off-the-shelf catalog lenses , which have the dual advantage of being inexpensive compared to a small custom production run as well as being immediately available. Stock lenses can be integrated into custom multi-element designs, yielding significant cost savings at a marginal sacrifice in performance. In some cases, stock lenses may not be practical for manufacturing a given application but may be suitable for fast prototyping. In addition, the readily available prescription data for most lenses and even many multi-element lenses are encouraging designers to use stock lenses.

Knowledge of manufacturing practices allows designers to construct the most economical solution. By investing some time at a local optics shop, designers can experience firsthand the fabrication techniques employed by an optician. Choices made during the design stage that appear inconsequential can prove to be crucial.

For example, the simple act of making elements equi-convex or equi-concave can eliminate problems and save costs in seemingly unrelated processes such as assembly. Ask any assembler how they feel about lenses that have nearly the same radii on their outer surfaces, and they will tell you stories of multiple tear-downs to correct for lenses mounted in the wrong direction. In order to avoid this added cost select equi-convex or equi-concave lenses. These lenses can also reduce the cost of test plates and reduce production time.

Any design starts with a given application and the known values associated with it. It’s the designer’s job to solve for the unknowns, typically by regarding certain specifications like radii as variables while holding other values constant. Values typically held constant include: diameter, center thickness, and glass material.

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