Spectacle Lens Types Compared: Single Vision, Bifocal, Trifocal, Progressive and Office Lenses, With an Order Checklist
Last updated: November 2026
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A counter guide for opticians, optometrists and ophthalmologists who dispense glasses in their own practice. It compares every common spectacle lens type side by side, shows which suits which patient, lists the measurements each type needs, and gives a checklist for taking the order so that the glasses are right the first time.
All lens types at a glance
| Lens type | What it gives | Best for | Drawbacks | Must measure |
|---|---|---|---|---|
| Single vision (distance) | One power for distance | Myopes, hyperopes and astigmats under 40; drivers; a second pair for presbyopes | Presbyopes need another pair to read | Distance PD (monocular for high powers), optical centre height |
| Single vision (near / readers) | One power for about 33–40 cm | Presbyopes who read for long periods; low budget | Distance is blurred; must be taken off to look up | Near PD (about 3 mm less than distance PD), optical centre height |
| Ready-made readers | Same sphere both eyes, standard PD | Emergency or spare pair for patients with no astigmatism or anisometropia | Wrong PD and no cylinder: eyestrain in many | Check that the sphere and PD suit the patient before recommending |
| Bifocal: flat-top (D-segment 25, 28 or 35 mm) | Distance above, near in a segment with a visible line | First bifocal, budget, high adds, people who cannot adapt to progressives | Visible line; no intermediate zone; small image jump | Distance PD, segment height, near inset |
| Bifocal: round (fused, often called Kryptok) | Round near segment | Low cost, very old wearers used to it | More image jump than flat-top; narrow reading area at the top | Distance PD, segment height |
| Bifocal: executive (Franklin) | Full-width segment across the lens | Desk work needing a wide near zone; accommodative esotropia in children | Heavy and thick; very visible line | Distance PD, segment height |
| Bifocal: blended (invisible) | Segment edge polished out | Patients who want no visible line but cannot afford or adapt to progressives | Blurred band where the line was; not for drivers who look down often | Distance PD, segment height |
| Trifocal (7×28, 8×35) | Distance, intermediate and near zones | Adds of +2.00 or more needing arm's-length vision (computer, music, shop counter) | Two lines; image jump at each | Distance PD, height of the top of the intermediate segment |
| Progressive (general purpose) | Smooth change from distance through intermediate to near; no line | Most presbyopes who want one pair for everything | Blur and swim at the sides; adaptation 1–2 weeks; costly; needs accurate fitting | Monocular PD, fitting height, frame size; for freeform designs also vertex, tilt and wrap |
| Progressive: short corridor | Same, with a shorter power change | Small, shallow frames | Narrower zones | Check the design's minimum fitting height |
| Office (occupational / degressive) | Wide intermediate and near zones, little or no distance | Computer users, doctors, tailors, cashiers, readers at a desk | Not for walking or driving | Near PD and heights as the design requires; agree the working distances |
| Double-segment (e.g. Double-D) | Near segment at the bottom and another at the top | Electricians, mechanics, librarians, painters who look up at near objects | Two near zones only; niche | Distance PD and both segment heights |
| Anti-fatigue (small near boost) | Single vision with a low add (+0.40 to +0.88) at the bottom | Pre-presbyopes with screen strain once refraction and binocular vision are normal | Evidence is limited; not a substitute for treating binocular problems | Monocular PD, fitting height |
| Myopia-control lenses (defocus designs) | Central distance correction with a ring of defocus | Children with progressing myopia, prescribed by the eye care practitioner | Must be centred on the pupil and worn full time; cost (see below) | Monocular PD and pupil height in a well-fitting frame |
Which lens for which patient
| Patient | First choice | Why |
|---|---|---|
| First-time presbyope, 40–48 years, low add | Progressive | Adapts most easily when the add is low |
| Long-time bifocal wearer, add +2.50, happy | Keep the bifocal | Switching late in life with a high add has the highest failure rate; offer a progressive only if the patient asks |
| Heavy computer or desk worker | Office lens as a second pair (or as the main pair at work) | Wider intermediate zone than any general progressive |
| Professional driver | Single-vision distance or a progressive with a wide distance zone | Clear far and side vision |
| Older person at risk of falls | Single-vision distance glasses for walking outside, plus readers | Lower segments of bifocals and progressives blur the ground and steps |
| High cylinder or oblique axis | Freeform (digital) progressive, or bifocal | Standard progressives add their own side astigmatism |
| Anisometropia of 1.50 D or more | Single vision, or a bifocal with slab-off; refer if unsure | Vertical prism imbalance when reading through the lower lens |
| Child with accommodative esotropia | Executive or large flat-top bifocal, segment top bisecting the pupil | The child must read through the add without effort |
| Very small, shallow frame chosen | Short-corridor progressive, or advise a deeper frame | A standard corridor will not fit; near zone is cut off |
| Patient who failed a progressive | Check measurements and fit first; then try office lens or bifocal | Most failures are fitting errors, not the patient |
Progressive lens types: standard, wide, extra wide and personalised
Every progressive has unwanted astigmatism (blur and swim) at the sides of the corridor and near zone. For a given add, the total amount cannot be removed (the Minkwitz theorem); designers can only move it. That is why names such as "wide", "extra wide" and "premium" exist: they describe how much clear zone you get and how far the blur is pushed to the edges. Each company uses its own names, so compare designs by their zone widths, not their labels.
| Type | How it is made | What the patient notices | Best for | Price |
|---|---|---|---|---|
| Standard (conventional) | Progressive surface moulded on the front of a semi-finished lens; the same design for everyone | Narrower intermediate and near zones; more swim at the sides | Low budget; low adds; easy adapters | Lowest |
| Short corridor | Power change compressed into a shorter height (minimum fitting height often 14–15 mm) | Reaches the near zone with less lowering of the eyes; zones slightly narrower | Small or shallow frames | Similar to standard or wide |
| Wide (digital / freeform back surface) | Design cut on the back surface by computer-controlled (freeform) machining, closer to the eye | Wider, clearer zones and less swim than standard | Most first-time and regular wearers | Middle |
| Extra wide / premium | Freeform on one or both surfaces with an optimised design; often several design variants | Widest intermediate and near zones; least distortion | Higher adds, computer users, previous adaptation problems | High |
| Personalised (position of wear) | Freeform design calculated for the wearer's vertex distance, pantoscopic tilt, wrap, frame shape and sometimes reading distance and head or eye movement | Most natural vision, especially in wrapped or tilted frames | Demanding wearers; high or oblique cylinders; anisometropia | Highest |
Other ways progressives differ
- Hard and soft designs. Hard designs have wide clear zones with blur that starts sharply at the edges; soft designs have narrower zones with gentler blur and less swim. Soft designs suit first-time wearers and high adds; hard designs suit people who read a lot and keep their head still.
- Distance-, near- or balanced-priority designs. Some designs give more width to distance (drivers, outdoor workers) and some to near and intermediate (desk workers).
- Corridor length. Longer corridors give a gentler power change and wider intermediate; shorter ones fit small frames. Always check the design's minimum fitting height.
- Office and room lenses (degressive or near-variable focus) are not general progressives; they give wide intermediate and near zones for desk work and are a second pair, not a replacement.
| Patient | Suggested progressive |
|---|---|
| First-time wearer, add +1.00 to +1.50, normal frame | Wide (freeform), soft design |
| Tight budget, low add, happy to adapt | Standard |
| Small or shallow frame | Short corridor (wide version if budget allows) |
| Add +2.25 or more, or long hours on a computer | Extra wide, or a general progressive plus an office lens |
| High or oblique cylinder, anisometropia, wrapped frame | Personalised (position of wear) |
| Failed with a standard progressive (after checking the fit) | Wide or extra wide with a soft design, or an office lens |
How to explain it at the counter: show the patient the zone diagram from the lens company or the one above, and say: "All progressives have blur at the sides. The more advanced lenses make the clear window wider and push the blur further away, so you move your head less."
Myopia-control spectacle lenses for children
These lenses correct distance vision through a central clear zone and add a pattern in the surrounding lens that slows eye growth, usually by adding peripheral myopic defocus or by reducing peripheral contrast. They are prescribed by the eye care practitioner for children whose myopia is progressing; the optician's job is to fit them exactly. Results below come from the main trials against single-vision lenses; real-world results are usually smaller, and several trials were funded by the manufacturers.
| Design (example) | How it works | Main trial result | Notes |
|---|---|---|---|
| DIMS: Defocus Incorporated Multiple Segments (Hoya MiyoSmart) | About 9 mm central clear zone; a honeycomb of small lenslets of +3.50 D in a ring around it | 2-year RCT: progression slowed by about 52% and axial elongation by about 62% | Benefit continued in long-term follow-up; most widely studied |
| HAL: Highly Aspherical Lenslets (Essilor Stellest) | About 9 mm central zone; 11 rings of aspherical lenslets creating a volume of myopic defocus | 2-year RCT: progression slowed by about 55%, more in children wearing them 12 hours or more a day | Wearing time matters; a stronger version (HALT MAX) is being studied |
| DOT: Diffusion Optics Technology (SightGlass) | Tiny dots scatter light and lower contrast on the peripheral retina | 12-month results: 0.48 D and 0.26 mm less progression than single vision | Longer-term effect appears smaller; no rebound reported after stopping |
| CARE: Cylindrical Annular Refractive Elements (Zeiss MyoCare) | Rings of cylindrical elements creating peripheral myopic defocus around a central zone | 2-year RCT: about 0.40–0.44 D and 0.17–0.20 mm less progression | Larger effect in older children |
| Executive bifocal with base-in prism | +1.50 D add with 3Δ base-in in each lens, segment top at the lower pupil margin | 3-year RCT: progression roughly halved in fast-progressing children | Cheaper, but cosmetically less popular; works best with near esophoria |
| Progressive lenses (standard) | Reduce accommodative lag at near | Small effect (about 0.2 D over 3 years, COMET) | Not a first choice for myopia control |
Do not undercorrect a myopic child to slow progression: it does not work and may speed it up. Older peripheral-defocus single-vision designs showed no overall benefit.
Fitting myopia-control lenses
- Use the exact lens prescribed; do not substitute another design or a single-vision lens.
- Choose a frame that stays put: good bridge fit, enough lens depth and width for the treatment zone, short vertex distance and normal tilt. Avoid frames that slide down the nose.
- Measure monocular PD and pupil height with the frame adjusted on the child's face; the central clear zone must sit over each pupil.
- Explain full-time wear: at least 10–12 hours a day, including school, and that looking out of the side of the lens may be slightly blurred, so the child should turn the head.
- Remind parents that glasses work best with other measures (2 hours outdoors daily, and atropine if prescribed), and that follow-up every 6 months with refraction and axial length is needed.
- Replace the lenses when the prescription changes by 0.50 D or more, or if they are badly scratched.
For the whole range of options, including atropine, contact lenses, ortho-k and red light, see myopia control in 2026.
How to prescribe and write the add
Always base the add on the patient's working distance and amplitude of accommodation. The table is only a starting point for a patient with normal accommodation for their age.
| Age (years) | Usual starting add |
|---|---|
| 40–45 | +0.75 to +1.25 |
| 45–50 | +1.25 to +1.75 |
| 50–55 | +1.75 to +2.25 |
| 55 and over | +2.25 to +2.50 (rarely more, except in low vision) |
- Give the lowest add that gives comfortable reading at the patient's own distance; check the range of clear vision, not only the nearest letter.
- The add is usually the same in both eyes. Recheck if your two adds differ by more than 0.50 D: usually one eye is under- or over-corrected for distance.
- Near-only spectacles = distance prescription + add (sphere changes, cylinder and axis stay the same).
- Intermediate (computer at 60–70 cm) is usually about half to two-thirds of the near add.
- Write the prescription clearly: sphere, cylinder, axis in three digits (e.g. 005), add, and prism with base direction for each eye. Write "DS" for a pure sphere and "plano" rather than leaving a gap.
Measurements for each lens type
| Lens type | Horizontal | Vertical |
|---|---|---|
| Single vision distance | Binocular PD, or monocular PD for powers over about ±4.00 D or any prism | Optical centre at the pupil, lowered about 1 mm for each 2° of pantoscopic tilt |
| Single vision near | Near PD (about 3 mm less than distance PD at 40 cm) | Optical centre about 2–5 mm below the pupil in primary gaze |
| Flat-top or round bifocal | Distance PD; segment inset about 1.5–2 mm per eye | Segment top at the lower lid margin (general); 1–2 mm lower for those who walk a lot; higher for heavy readers |
| Executive bifocal for children | Distance PD | Segment line bisecting the pupil (or at the lower pupil margin) |
| Trifocal | Distance PD | Top of the intermediate segment at the lower pupil margin |
| Progressive | Monocular PD to each pupil centre (use a pupillometer or measure on the frame) | Fitting height from pupil centre to the lowest point of the lens rim, with the frame adjusted on the face; must meet the design's minimum (often 14–18 mm; check the lens chart) |
| Office lens | Monocular near or distance PD, as the design asks | As the design asks; usually at the pupil or a set distance from it |
Taking the order: step-by-step checklist
At the counter, before the patient leaves
- Read the prescription carefully. Check the date, the patient's name and that every field is filled. Watch for plus and minus cylinder, axis written in three digits, and the add written only once if it is the same in both eyes.
- Read the old glasses on the lensometer. Compare them with the new prescription. If the sphere or cylinder changes by more than about 0.75 D, or the axis moves more than about 10° in a cylinder of 1.00 D or more, warn the patient about adaptation and check with the prescriber if the change is not explained.
- Ask how the glasses will be used. Job, screen distance, driving, hobbies, reading posture, and what lens type was worn before and whether it worked.
- Choose the lens type from the tables above and explain the trade-offs honestly, including adaptation time for progressives.
- Choose a frame that suits the prescription and the design. Enough depth for the progressive or bifocal; small, round, well-centred frames for high minus; avoid rimless and semi-rimless with brittle materials.
- Choose the material and coatings (polycarbonate or Trivex for children, sport and rimless; high index for high powers; AR coating with high index; hard coat on all plastic lenses).
- Adjust the frame on the face first, then measure monocular PD and heights. Record frame size (A, B, DBL), pantoscopic tilt, wrap and vertex distance for freeform lenses.
- Write the order fully: prescription, lens design and brand, index, coatings, tint, PDs, heights, frame measurements, and any special request (slab-off, prism, base curve to match the old pair in anisometropia).
- Counsel the patient: how to use the lens, how long adaptation takes, what your remake or non-adaptation policy is, and the delivery date.
- Double-check the order slip against the prescription before sending it to the lab. Most remakes come from transcription errors.
At delivery
- Verify each lens on the lensometer against the order and the tolerances (see the dispensing reference).
- For progressives, check the markings: fitting cross, prism reference point and the engraved circles; re-mark from the engravings if needed.
- Fit the frame: even height, correct tilt, comfortable nose pads and sides.
- With the patient looking straight ahead, the fitting cross (or segment top) must sit where you measured it.
- Check distance and near vision with the patient's own reading material. Teach progressive wearers to point the nose at what they want to see and to lower the eyes, not the head, to read.
- Remove the ink markings only after you are happy with the fit.
When the patient comes back unhappy
| Complaint | Most likely cause | What to do |
|---|---|---|
| Progressive: distance blurred, patient lowers the chin | Fitting cross too high, or distance power too plus | Remeasure height on the adjusted frame; check the prescription |
| Progressive: tilts head back to read | Fitting height too low, add too weak, or frame sitting low | Adjust the frame up; remeasure; check the add |
| Progressive: reading area narrow on one side | Monocular PD wrong, or frame not centred | Check each PD; straighten the frame |
| Progressive: swimming at the sides | Normal early on; or wrong tilt, wrap or design for the patient | Reassure for 1–2 weeks; check fit; consider a softer design |
| Bifocal: line gets in the way when walking | Segment too high | Lower the segment (remake) or teach to lower the chin when walking |
| Bifocal: has to lift the chin to read | Segment too low | Raise the frame or remake with a higher segment |
| Floor seems tilted or curved | New or changed cylinder or axis; base curve changed | Check against the old pair; refer back to the prescriber if the change is large |
| Double vision or pulling | Unwanted prism from wrong PD or centration | Measure optical centres against the PD; check tolerances |
Care advice to give every patient
- Rinse lenses under running water, wash with a drop of mild soap, then dry with a clean microfibre cloth. Do not wipe dry lenses with clothes or tissue.
- Use both hands to put on and take off the glasses so the frame stays straight.
- Keep them in a hard case, lenses facing up when put down, and never on a car dashboard: heat cracks (crazes) coatings.
- Avoid hair spray, perfume and spirit-based cleaners on coated lenses.
- Come back for a free adjustment if the glasses slip or feel uneven.
Practical pearls
- Read the old glasses on the lensometer before taking every order: it explains most complaints before they happen.
- Measure progressive heights only after the frame has been adjusted on the face, with the patient looking straight ahead at your eyes on the same level.
- If a patient has failed a progressive, check your own measurements first; most "non-adapters" were fitted wrongly.
Where students slip
- Using binocular PD for a progressive or a high prescription.
- Ordering a standard progressive in a frame too shallow for its minimum fitting height.
- Giving a stronger add than needed: it shortens the reading distance and narrows the intermediate zone.
Test yourself: flip cards
Quick quiz
Related: Spectacle Lens Designs: Aspheric, Bifocals and Progressive Lenses (Fitting and Troubleshooting), Frame Selection and Spectacle Fitting: Boxing System, PD, Fitting Height, Tilt and Wrap, Spectacle Dispensing Reference: PD, Fitting Height, Tolerances, Spectacle Non-Tolerance: A Step-by-Step Troubleshooting Guide for Optometrists, Sunglasses, Polarised and Photochromic Lenses, Tints and Night-Driving Glasses: A Practical Guide. Back to the optometry curriculum.
Key sources
- Jalie M. Ophthalmic Lenses and Dispensing. 3rd ed. Butterworth-Heinemann; 2008
- Brooks CW, Borish IM. System for Ophthalmic Dispensing. 3rd ed. Butterworth-Heinemann; 2007
- Haran MJ, et al. Effect on falls of providing single lens distance vision glasses to multifocal glasses wearers: VISIBLE randomised controlled trial. BMJ. 2010;340:c2265
- ANSI Z80.1-2020. Prescription Ophthalmic Lenses: Recommendations
- Lam CSY, et al. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: a 2-year randomised clinical trial. Br J Ophthalmol. 2020;104:363-368
- Bao J, et al. Spectacle lenses with aspherical lenslets for myopia control vs single-vision spectacle lenses: a randomized clinical trial. JAMA Ophthalmol. 2022;140:472-478
- Myopia Profile. ARVO 2025 recap: updates in myopia control spectacles (MyoCare 2-year RCT, DOT, HAL)
- Rappon J, et al. Control of myopia using diffusion optics spectacle lenses: 12-month results of a randomised controlled, efficacy and safety study (CYPRESS). Br J Ophthalmol. 2023;107:1709-1715
- Cheng D, et al. Effect of bifocal and prismatic bifocal spectacles on myopia progression in children: three-year results of a randomized clinical trial. JAMA Ophthalmol. 2014;132:258-264
- Gwiazda J, et al. A randomized clinical trial of progressive addition lenses versus single vision lenses on the progression of myopia in children (COMET). Invest Ophthalmol Vis Sci. 2003;44:1492-1500
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