TLC-266M2 Trial lens kit, 266 color-coded lenses
A 266-lens trial lens kit with color-coded metal rims: red for minus lenses, black for plus. Plus and minus spheres from 0.12 to 20.00 D and cylinders from 0.12 to 6.00 D, two of each, prisms from 0.5 to 8 Δ and 14 auxiliary lenses, Ø38 mm with a 36 mm clear aperture. Choose a resin or wooden tray and an aluminum or leather case.
Delivery, packing and documents
What is in the TLC-266M2
Spheres to ±20 D
Plus and minus spheres, two of each: 0.12 D, then 0.25 D steps to 6.00 D, 0.50 D steps to 10.00 D, and 11, 12, 13, 14, 16, 18 and 20 D.
Cylinders to ±6 D
Plus and minus cylinders, two of each: 0.12 D, then 0.25 D steps to 4.00 D, and 4.50, 5.00 and 6.00 D.
Prisms 0.5 to 8 Δ
Two each of 0.5, 1 and 2 prism diopters, and one each of 3, 4, 5, 6, 7 and 8 Δ.
14 auxiliary lenses
Red and green filters, two occluders, a plano lens, two Maddox rods, a frosted lens, a cross-line lens, two pinholes, two stenopaeic slits and a cross cylinder.
Color-coded metal rims
Red rims for minus lenses and black rims for plus lenses, with the power on each handle tab.
Your choice of tray and case
A resin or wooden tray with a slot for every lens, in an aluminum or leather case.
A closer look at the TLC-266M2
Tray layout
Minus spheres and cylinders on the left, plus on the right, and the auxiliary lenses and prisms in the center, each slot labeled with its power.
Color-coded rims
Red rims for minus lenses and black rims for plus lenses, with the power on the handle tab, so the right lens comes out of the tray first time.
A slot for every lens
Each lens stands in its own slot, clear of its neighbors.
Lockable aluminum case
The aluminum case closes with combination locks. A leather case is also available.
TLC-266M2 in figures
Published specifications. Anything not listed here is confirmed in writing on your quotation, never estimated.
Case dimensions and weight depend on the tray and case you choose, and are confirmed in writing on your quotation.
TLC-266M2
- Configuration
- 266A, 266 lenses
- Lens size
- Ø38 mm outer, Ø36 mm clear aperture
- Rims
- Color-coded metal (red minus, black plus)
- Tray
- Resin or wood
- Case
- Aluminum or leather
Lens powers
- Spheres, plus and minus
- 0.12; 0.25 to 6.00 D in 0.25 D steps; 6.50 to 10.00 D in 0.50 D steps; 11, 12, 13, 14, 16, 18, 20 D (two of each)
- Cylinders, plus and minus
- 0.12; 0.25 to 4.00 D in 0.25 D steps; 4.50, 5.00, 6.00 D (two of each)
- Prisms
- 0.5, 1 and 2 Δ (two of each); 3, 4, 5, 6, 7 and 8 Δ (one of each)
Auxiliary lenses
- Red filter (RF)
- 1
- Green filter (GF)
- 1
- Occluder (BL)
- 2
- Plano lens (PL)
- 1
- Maddox rod (MR)
- 2
- Frosted lens (FL)
- 1
- Cross-line lens (CL)
- 1
- Pinhole (PH 1.5)
- 2
- Stenopaeic slit (SS 1.5)
- 2
- Cross cylinder
- 1
Choosing and using a trial lens set
How it works
A trial lens set is the lens library for subjective refraction. Lenses go into a trial frame, or are held in front of the eye, to refine a prescription, to try it out before glasses are made, or to over-refract an existing pair. ISO 9801 sets the requirements for trial case lenses used to determine the refractive error of the eye.
A trial frame suits patients who find a phoropter difficult: young children, older and low-vision patients, wheelchair users, and anyone with a high prescription, because you can see the patient and set the vertex distance yourself. Put the strongest sphere in the back cell, closest to the eye, and record the vertex distance; for powers of ±5.00 D and above it should go on the prescription.
The auxiliary lenses cover the rest of the routine. If vision improves through a pinhole, uncorrected refractive error is part of the problem. The cross cylinder refines cylinder axis and power; for every 0.50 D change in cylinder, change the sphere by 0.25 D the other way to keep the spherical equivalent.
Check before you order
- Ranges against the prescriptions you see: spheres to ±20.00 D, cylinders to ±6.00 D and prisms to 8 Δ here.
- Lens size, which must fit your trial frame: Ø38 mm rims with a 36 mm clear aperture.
- How quickly staff can tell plus from minus lenses in the tray.
- Which auxiliary lenses are included.
- Tray and case: a wooden tray and leather case for the exam room, or an aluminum case if the set travels.
Good practice
- Return every lens to its own slot straight away, so the next refraction does not start with a search.
- Place the strongest sphere in the back cell of the trial frame, nearest the eye.
- Measure and record the vertex distance for prescriptions of ±5.00 D and above.
- After changing the cylinder with the cross cylinder, rebalance the sphere to keep the spherical equivalent.
- Check any lens you are unsure of on a lensmeter before relying on it.
Care and maintenance
- Handle lenses by the rim or tab, not the glass, and clean them with a soft lens cloth.
- Keep the case closed and dry when the set is not in use.
- Check powers on a lensmeter from time to time, and replace chipped or scratched lenses.
Background sources: ISO 9801:2009, Ophthalmic instruments: trial case lenses (ISO) · Trial frame refraction: more than just “1 or 2?” (Cybersight, Orbis) · Jackson cross cylinder (StatPearls, NCBI Bookshelf) · Visual acuity (StatPearls, NCBI Bookshelf) · Essential course in dispensing, part 14 (Optician)
Often ordered with the TLC-266M2
TLC-266M2 questions
What is in the 266-lens set?
Plus and minus spheres from 0.12 to 20.00 D and cylinders from 0.12 to 6.00 D, two of each; prisms from 0.5 to 8 Δ; and 14 auxiliary lenses, including red and green filters, occluders, Maddox rods, pinholes, stenopaeic slits and a cross cylinder.
How is the TLC-266M2 different from the TLC-266M1?
The lens powers match. The TLC-266M2 has red and black color-coded rims and a choice of resin or wooden tray and aluminum or leather case.
Will the lenses fit my trial frame?
The lenses are Ø38 mm. Check that your trial frame takes 38 mm trial lenses, or send us its model and we will check for you.
Which tray and case should I choose?
A wooden tray and leather case suit a fixed exam room; an aluminum case protects the set if it travels. Tell us your choice and we quote it.