Frame types and parts

Spectacle Frame Type and Parts

1. Frame Types and Parts Parth Vora M-1

2. Basic parts 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 consist of the front , which in one form or another contains the lenses, and the temples , which attach to the front and hook over the ears to help hold the spectacles in place.

3. Frame front

4. Bridge: That area of the frame front between the lenses that rests on the nose. E yewire or rim: The rim going around the lenses is known as the. Endpieces : The outer areas of the frame front, to the extreme left and right where the temples attach. A few plastic frames may still have a metal shield on the front of the endpiece to which rivets are attached to hold the hinge. The hinges hold the temples to the front, and consist of an odd number of inter fitting barrels, the total number being 3, 5 , or 7 .

5. Parts of temple

6. 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 . portion beyond the bend and behind the ear is referred to as the earpiece .

7. Frame types Plastic Metal Nylon cord frames Combination Half eye Rimless Semirimless Numont

8. Plastic frame Thermosetting Material begins as liquid & becomes solid during manufacturing process Once product has been manufacture, it never again soften to any significant extent Thermoplastic Has property of softening when heated & hardening when cooled Basic structure of material remain same E.g. polymethyl nitrate, cellulose nitrate, cellulose acetate.

9. Metal frame All metal parts Except nose pads and posterior temple section Lens holder is fixed with screw Fixed design/ can’t customize shape of lens

10. Nylon cord frame

11. Combination frame

12. Half eye frame

13. Rimless frame

14. Numont frame

15. Balgrip frame

16. Plastic frame material Cellulose nitrate Cellulose acetate Cellulose aceto propinate Optyl Nylon polyamide

17. Metal frame materials Gold Aluminum Nickel silver Monel Titanium Stainless steel Bronze

18. Other materials Carbon fiber Rubber Polycarbonate

19. Bridge types The bridges area of plastic frame is performed and sits directly on the bridge of the nose . Plastic bridges Saddle bridge Modified saddle bridge Keyhole bridge Metal bridges Saddle bridge Pad bridge Strap bridge

20. 1)SADDLE BRIDGE: Shaped like a saddle in a smooth curve And follows the bridge of the nose. This separates the weight of the frame evenly over the sides and crest of the nose.

21. 2)MODIFIED SADDLE BRIDGE: It’s look like same as the saddle bridge when viewed from the front. The difference is that there are nose pads that are part of the back of the bridge. These pads helps to carry some of the weight of the frame.

22. 3)KEYHOLE BRIDGE: Shaped like an old fashioned keyhole. At the top,thebridge flares out slightly. The bridge rests on the sides of T he nose , but not on the crest .

23. Metal saddle bridge Old style saddle bridge

24. Pad bridge Commonly used in metal frames Nose pads are attached to the frame by metal and pad arms Pads alone support weight of glasses

25. Strap bridge Metal frame with clear plastic saddle type bridge Alternative to adjustable or replace nose pads

26. Plastic endpieces construction: There are three general types of endpiece construction in plastic frames. The most common endpiece construction is Butt type , in which the front is straight and the temple butt is flat and both meet at a 90 degree angle.

27. The mitre endpiece causes the frame front contact area and temple butt to meet at a 45 degree angle. In the turn-back type,the frame front bends around and meets the temple end to end.

28. Temple construction: Skull Liberty Convertible Riding bow Comfort cable

29. Temple construction: 1)SKULL TEMPLE: Bend down behind the ears, follow the contour of the skull and rest evenly against the skull. 2)LIBRARY TEMPLE: Generally straight and do not bend down behind the ears. Hold the glasses primarily through light pressure against the side of the skull.

30. 3)CONVERTIBLE TEMPLE: T he temple may be easily straightened out and then re-bent to the wearer. Used either as library or skull temples depending on the bent . 4)RIDING BOW TEMPLE: Curve around the ear following the crotch of the ear where the ear and head meet and extend to the level of earlobe. made by plastic material Used mostly for children’s safety purpose.

31. 5)COMFORT CABLE TEMPLE: Same as riding bow temples, but made from a springy cable of coiled metal, sometimes inside a plastic or silicone sleeve. Used for physically active wearers, children, and people with high prescriptions(heavy lenses ).

32. Metal frame materials Gold Gold having all these property except low cost. Types Fine gold : 100% pure gold (24 karat) Solid gold : gold + base metal evenly mixed (10 karat) Gold filled : base metal in side solid gold coating (1/20) Gold plated : a base metal thinly plated with gold (1/50)

33. Aluminium Advantages Stain resistance Strong & light weight Can painted many attractive colors Disadvantages Doesn’t solder or weld well Requires screw or rivets It conduct heat readily and become cold in winter No flexibility

34. Nickel silver 50% Copper 25% Nickel(whitish appearance) Zink & other metals (strength) Material is rigid & lustrous It mostly use base metal in gold filled

35. M onel Whitish in color 68% nickel,30% copper,2% iron Traces of silicon, carbon & sulfur Can be coated with many color and corrosion resistant Mostly use for temples & bridges

36. Bronze frames It is anti corrosive, light & comfortable Alloy of copper & iron Pliable , tough Mechanically strong

37. Stainless steel 74% iron 18% chromium 8% nickel Advantages Durable, flexible, strong, nonmagnetic Resistant to oxidation & corrosion Endless color availability Well suited for temple flexibility to adjust & align Disadvantages Can’t repaired expensive

38. Taitanium Advantages Lightweight, flexible Corrosion resistant Abrasion resistant Thinnest of all metals Hypoallergenic Disadvantages Expensive Limited color Hard to solder or weld

39. Cellulose nitrate( Zylonite ) More tougher can be made thinner frame Better dimensional stability It accepts a good polish but is flammable if brought to a sufficiently high temperature. Banned by FDA and is no longer used.

40. Cellulose acetate Thermo plastic polymers Produced in pre-colored sheets and frames are then cut from this sheets using various cutting jigs. Metal cores are inserted in the temples to provide greater strength Advantages Low flammability Faster production & more color options Easily polished and repaired Disadvantages Allergic reaction by uncoated materials Brittle with age Will blister if over heated To make any adjustment cellulose acetate should be heated at 70 degree Celsius and then manipulated only when soft.

41. Cellulose aceto-proprionate Also a thermo plastic material Produced by a forced injection molding process, fewer steps for production and less wastages Material of choice because it is much cheaper to produce Metal cores in the temples 5/4 of wt. of cellulose acetate, low flammability, easy produced, can be made thinner than acetate frames. Disadvantages Less color stability unless it is covered with high quality frame coating material Frames become brittle with age Needs more heat than cellulose acetate

42. Polymide Means more than one amide, an organic compound of nylon family, produced like propionate. Has considerable mechanical stability and can be made even thinner than proprionate Advantages Lighter, hypoallergenic, low flammability, very hard so durable, can be made thinner than other plastic frames Disadvantages Will shrink overheated Can not be repaired Easily affected by heat & Best fitted in cold

43. Optyl Thermo elastic material and has a very powerful memory and will always return to its original shape with heat. Has considerably greater durability than other frame material Advantages Very hard, durable surface, hypoallergenic Non flammability, dimensional stability 30% lighter than cellulose acetate in weight Will not age Disadvantage Will return to it’s original shape if overheated, losing any adjustment Can’t be repaired

44. Nylo n Tough material so used in protective spectacles where they receive tough treatment Highly flexible Previously used as sports eyewear Disadvantage Difficult to adjust & not attractive as other materials

45. Carbon fiber Very tough, yet brittle frame material Mainly used for the frame front Mad from nylon mixed with a fiber of potassium titanate Advantages Light weight , strong , low flammability Disadvantage Not adjustable Color opaque & limited Breakage on cold weather

46. Polycarbonate Sport and safety eyewear Non prescription, lens and frames are molded as one piece Impact resistant Shield type glasses Disadvantages Non adjustable

47. Rubber Some sports eyewear and sunglasses frames may be made from a combinations of nylon and rubber. These frames are flexible and will return to their original shape. Not adjustable.