Trial Lens Sets, Cross Cylinders & Prisms
Trial lens sets for subjective refraction in the shop, from a 68-lens set to full 266-lens sets in metal or plastic rims, plus Jackson cross cylinders and a 48-prism set.
Every figure is a published specification; anything not listed is confirmed on your quotation.
Five trial lens sets
Four 266-lens sets that differ in rims, aperture, tray and case, and a compact 68-lens set.
TLC-266M1
Trial lens set, 266 metal-rim glass lenses, spheres to ±20 D.- Lenses
- 266
- Rims
- Metal
- Spheres
- ±0.12 to ±20.00 D
- Case
- Combination lock, 560 × 340 × 90 mm
TLC-266M2
266-lens trial kit, red and black color-coded rims.- Lenses
- 266
- Rims
- Color-coded metal
- Tray
- Resin or wood
- Case
- Aluminum or leather
TLC-266M3
266-lens trial set, gold and silver rims.- Lenses
- 266
- Rims
- Gold and silver metal
- Tray
- Resin or wood
- Case
- Aluminum or leather
TLC-232P
266-lens trial box, red and black plastic rims, Ø30 mm aperture.- Lenses
- 266 (266A or 266B)
- Rims
- Color-coded plastic
- Aperture
- Ø30 mm
- Case
- Aluminum, resin tray
JP-68
Compact 68-lens trial set, Ø36 or Ø26 mm aperture.- Lenses
- 68
- Rims
- Metal or plastic
- Aperture
- Ø36 or Ø26 mm
- Case
- Leather, wooden tray
Which trial lens set?
The 266-lens sets carry the same powers (TLC-232P also comes as 266B); choose by rim style, aperture, tray and case.
| TLC-266M1 | TLC-266M2 | TLC-266M3 | TLC-232P | JP-68 | |
|---|---|---|---|---|---|
| Lenses | 266 | 266 | 266 | 266 (266A or 266B) | 68 |
| Spheres | ±0.12 to ±20.00 D | ±0.12 to ±20.00 D | ±0.12 to ±20.00 D | to ±20.00 D (266B: to +12.00 D) | On quotation |
| Cylinders | ±0.12 to ±6.00 D | ±0.12 to ±6.00 D | ±0.12 to ±6.00 D | ±0.12 to ±6.00 D | On quotation |
| Prisms | 0.5 to 8 Δ | 0.5 to 8 Δ | 0.5 to 8 Δ | 0.5 to 8 Δ | |
| Clear aperture / outer | Ø36 / Ø38 mm | Ø36 / Ø38 mm | Ø36 / Ø38 mm | Ø30 / Ø38 mm | Ø36 or Ø26 / Ø38 mm |
| Rims | Metal | Color-coded metal | Gold and silver metal | Color-coded plastic | Metal or plastic |
| Tray and case | Slotted tray, combination-lock case | Resin or wood; aluminum or leather | Resin or wood; aluminum or leather | Resin; aluminum | Wood; leather |
Cross cylinders and prisms
CC-02 / CC-03 / CC-04
Jackson cross cylinders, sets of 2, 3 or 4, ±0.25 to ±1.00 D.- Models
- CC-02 / CC-03 / CC-04
- Cylinders per case
- 2, 3 or 4
- Powers
- ±0.25 to ±1.00 D
- Case
- Aluminum
PR-48
48 loose prisms, 0.25 to 10 Δ, aluminum case.- Prisms
- 48
- Range
- 0.25 to 10 Δ
- Rims
- White plastic
- Case
- Aluminum, wooden tray
Using trial lenses well
Where a trial set helps
A trial frame and trial lenses suit patients who find a phoropter difficult: young children, older and low-vision patients, wheelchair users, and high prescriptions, because you can see the patient and set the vertex distance yourself. They are also used to show a new prescription before glasses are made.
Vertex distance
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.
Cross cylinders
A Jackson 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.
Standards
ISO 9801 sets the requirements for trial case lenses, full and reduced aperture, used to determine the refractive error of the eye.
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) · Essential course in dispensing, part 14 (Optician)
Trial lens questions
What is the difference between the three 266-lens sets?
The lens powers are the same. The TLC-266M1 has metal rims in a combination-lock case; the TLC-266M2 has color-coded metal rims and the TLC-266M3 gold and silver metal rims, each with a resin or wooden tray and an aluminum or leather case.
Will the lenses fit my trial frame?
The trial lenses are Ø38 mm across. Check that your trial frame takes 38 mm trial lenses, or send us its model and we will check for you.
Do I need a separate cross cylinder if my set has one?
Each 266-lens set includes one cross cylinder. The CC-02, CC-03 and CC-04 sets add hand-held cross cylinders in more powers, up to ±1.00 D.
Is a trial frame included?
Not as standard. Add one of our trial frames to the same order.