Frames

FRAMESIntroduction parts Types

INTRODUCTION

The frame is that portion of the spectacles that holds the lenses

containing the ophthalmic prescription in their proper

position in front of the eyes.

A frame generally consists of the

front, which contains the lenses,

temples, which attach to the front and hook over the ears to help hold

the spectacles in place.

Frame FrontsThat area of the frame front between the lenses

that rests on the nose is the bridge.

The rim going around the lenses is known as the eyewire or rim.

The outer areas of the frame front, to the extreme left and right where the temples attach, are known as the endpieces .

Lugs: They are projection on the sides to which the side piece are attached

HingesThe hinges hold the temples to the

front, and consist of an odd number of interfitting barrels, the total number

being three, five, or seven

Nose padsSome frames have nose pads, which are plastic

pieces that rest on the nose to support the frame. These may be directly attached to the frame or to connecting metalpieces known as

guard arms or pad arms

Temples The portion of the temple that is nearest

its attachment to the front is known as the butt portion or butt end.

The place on the temple where it first bends down to go over the ear is called

the bend.

The portion of the temple between the butt end and the bend is called the

shank or shaft

and that portion beyond the bend and behind the ear is referred to as the earpiece, bent-down portion, or curl

TYPES OF FRAMES

Frames without an eyewire going completely around the lens are called mountings. Lenses are “inserted” into frames, but

“mounted”into mountings

PlasticPlastic frames are made of some type of plastic material.Plastic

frames were occasionally referred to as shell frames, dating back to the time when eyeglass frames were made of tortoise

shell

MetalMetal frames are those made of all metal parts, except for the nose pads and the posterior temple sections, which are plastic

covered. The eyewire runs completely around the lens.

Nylon cord frames

Nylon cord frames, sometimes called string mounted frames

or nylon supras hold the lenses in place by means of a

nylon cord that fits around the edge of the lens. This

gives the glasses the appearance of being rimless. Usually the top of the lens is fitted into the upper rim of the frames. The rest of the lens has a small groove cut into an otherwise flat edge

Combination frames

Combination frames are commonly frames having a metal chassis and plastic top rims and temples . The chassis includes the eyewire and center or

bridge section

Half-eye

Half-eyes are frames made especially for those who need

a reading correction but no correction for distance. They are constructed to sit lower

on the nose than normal,and are only half as high as normal glasses. This allows the wearer to look over the

top of the glasses. They may be of plastic, metal, or even

nylon cord construction

Rimless mountings

Rimless mountings hold the lenses in place by some

method other than eyewires or nylon cords. Often screws

are used, but cement, clamps, and plastic posts

have been used. Most rimless mountings have two

areas of attachment per lens, one nasally and one

temporally Rimless mountings are sometimes

referred to as 3-piece mountings

Semi rimless mountings

Semi rimless mountings are similar to the rimless except for a metal reinforcing arm,

which follows the upper posterior surface of the lens and joins the centerpiece of

the frame to the endpiece. The centerpiece of a mounting

consists of bridge, pad arms, and pads

Numont mountings

Numont mountings hold the lenses in place only at their nasal

edge. They are seldom seen today. The lenses are attached at the bridge area and the temples are attached to a metal arm that

extends along the posteriorsurface temporally. Thus

there is only one point of attachment per lens . Currently most dispensers refer to any of

these three variations of a rimless mounting as “rimless.” They do not differentiate between the

three

Balgrip mountings

Balgrip mountings secure the lens in place with clips

attached to a bar of tensile steel that fits into a nasal and a temporal notch on each side of the lens Notches are now

more often used in combination with drilled holes in rimless mountings to lend

stability to the mounting

Bridges typesBridge Area:The bridge area of a frame can be constructed of

either plastic or metal. Plastic Bridges

The bridge area of a plastic frame is preformed and sits directly on the bridge of the nose Bridge adjustments for

certain plastics, such as nylon, carbon fi ber and polyamide, are not possible

Saddle

Modified saddle

Key hole

saddle bridge

The saddle bridge closely follows the contour of the

nose, evenly spreading the weight of the frame

  The saddle bridge is shaped

like a saddle in a smooth curve and follows the bridge

of the nose . This spreads the weight of the frame

evenly over the sides and crest of the nose

Modified saddle

The modified saddle bridge has fixed nose pads attached at the back to increase the weight-bearing area of the

frame  In the modified saddle, the bridge area looks much the same as the saddle bridge

does when viewed from the front. The difference is that there are nose pads that are

part of the back of the bridge. These pads help to carry some

of the weight of the frame .

Keyhole bridge

The keyhole bridge is shaped like an old-fashioned keyhole. At the

top, the bridge flares out slightly. The bridge rests on the sides of the nose,

but not on the crestBesides having an identifying

shape, the keyhole bridge supports the frame weight upon

pads

Metal Bridges

The bridge commonly used in metal frames is the pad bridge .

In the pad bridge, nose pads are attached to the frame by

metal pad arms.

In this case, the pads alone support the weight of the

glasses. When a metal frame is equipped with a clear plastic

saddle-type bridge, the bridge type is referred to as a comfort

bridge

Metal and rimless frames were, and sometimes still are, constructed with a

metal saddle bridge(W bridge)

Endpiece ConstructionEndpiece construction, like the

bridge area construction, can be of either plastic or metal.

Plastic Endpieces Construction

There are three general types of endpiece construction in plastic

frames The most common endpiece

construction is the butt type(type 1) in which the front is straight and

the temple butt is flat, and both meet at a 90-degree angle.

Type 2:The mitre endpiece causes the frame front contact

area and temple butt to meet at a 45-degree angle

Type 3:In the turn-back type, the frame front bends around and meets the temple end to

end.

Metal Endpiece Construction

The traditional metal endpiece has a construction similar to the turn-back endpiece of the plastic frame

Instead of an endpiece, some frame fronts and temples are made as one continuous piece

Temple Construction

Temples also vary greatly in their construction. In general, there

are five major categories

Type 1:Skull temples bend down behind the ear and follow the contour of the skull, resting

evenly against it. The bent-down portion is narrower at the top of the ear and widens toward the

end

2.Library temples usually begin with an average width at the butt and

increase in width posteriorly. They are practically straight and hold the

glasses on primarily by pressure against the side of the head. They are also known as straight-back

temples.

3. Convertible temples were originally designed so they could be

bent down to take on the form of skull temples, and “converted” from

the straight-back to the skull design. Because this temple is

versatile and can be made to fit people with a variety of temple

length requirements, it is commonly used.

4. Riding bow temples curve around the ear, following the crotch of the

ear where the ear and the head meet and extend to the level of the earlobe. They are sometimes used

in children’s and safety frames

5. Comfort cable temples are shaped the same as riding bow

temples, but are of metal construction with the curl, or

behind the ear portion, constructed from a flexible coiled cable

DESIGNED & PRESENTEDBY

YOGAPRIYA.VB.opt(IIIyr)