Trial Lenses for Vision Correction | Generated by AI
English Term for “验光插片”
The items you’re referring to—”验光插片” (yàn guāng chā piàn)—are called trial lenses or optometry trial lenses in English. These are individual lens pieces (often in a set or kit) used in a trial frame (a adjustable frame that holds the lenses in front of your eyes) for testing and simulating different eyeglass prescriptions during an eye exam. They come in various powers for sphere (myopia/hyperopia), cylinder (astigmatism), and sometimes prism or axis adjustments. They’re typically made of glass or plastic, with powers ranging from +0.25 to -6.00 or higher in 0.25D increments (D = diopters, the unit for lens strength). You insert them into slots in the trial frame to test combinations.
These are not for everyday wear but for experimentation, like your myopia reversal setup. You can buy a basic trial lens kit online (e.g., from optical suppliers like Amazon or optometry stores) for $50–200, including a trial frame. A full professional set has 40–60 lenses, but for your personal experiment, you don’t need the entire pro kit—just a subset covering your range (-0.25 to -6.00 for spheres and cylinders).
Important Disclaimer: I’m not a doctor or optometrist. This is not medical advice. Myopia reversal experiments like yours are anecdotal and not scientifically proven to reverse eye changes permanently. Consult an eye care professional before making changes to your vision correction, especially since improper lenses can strain your eyes, cause headaches, or worsen vision. Your data shows both eyes at 0.9 vision (which is good, about 20/22), so monitor closely and stop if you notice issues.
Your Prescription Summary
Based on your table (assuming standard notation: myopia = spherical power, astigmatism = cylindrical power; axis not specified, so we’ll keep it general):
- Left Eye (OS): Full correction = -3.00D sphere (myopia) + -1.00D cylinder (astigmatism).
- Right Eye (OD): Full correction = -5.00D sphere (myopia) + -1.00D cylinder (astigmatism).
- Both eyes: Dated 2025.08.30 (future date? Assuming it’s a projection or typo), vision 0.9.
For your experiment, you’re following the “under-correction” principle: Use glasses with 1.50–2.00D less myopia correction (weaker negative sphere) for close work (phone/laptop at ~0.3–0.5m) to encourage eye muscle relaxation and prevent eyeball elongation. Keep full prescription for distance tasks (driving/TV). Astigmatism correction can stay the same or be slightly reduced if it causes blur, but test it.
- Why under-correct? As you noted, full-correction lenses make close objects too clear, over-focusing the eyes and potentially worsening myopia. Under-correction aims for “just barely clear” vision at your working distance (e.g., phone at arm’s length). Your formula (degree = 100 / distance in meters) is a rough guide: For a laptop at 0.5m to be just clear, you’d want ~ -2.00D effective power.
- Expected progress: As you said, aim for slow improvement (~0.25D per 3 months). Slightly blurry is okay—it’s part of the process.
- For phone/laptop: These are close tasks, so under-correction (1.50–2.00D reduction) should make them “just clear enough” without strain. Test at your typical distance (e.g., 40cm for phone).
Recommended Trial Lens Set for Your Experiment
You don’t need a huge set—focus on lenses covering -0.50 to -5.50D for spheres (myopia) and -0.50 to -1.50D for cylinders (astigmatism), in 0.25D steps. A basic personal kit might include 20–30 pieces total (10–15 per eye type). Here’s a minimal, targeted list of pieces you’d need (total ~24 lenses: 12 spheres + 12 cylinders). This covers full Rx, under-corrections, and testing variations for phone/laptop clarity. Buy plus (+) power spheres too if you want to simulate reading adds later.
Minimal Spheres Needed (for Myopia Testing, Both Eyes)
These handle the main myopia reduction. Get one of each power (neutralizes if not used).
- -0.50, -0.75, -1.00, -1.25, -1.50, -1.75, -2.00, -2.25, -2.50, -2.75, -3.00, -3.25, -3.50, -3.75, -4.00, -4.25, -4.50, -4.75, -5.00, -5.25, -5.50 (21 total, but you can skip extremes if budget-limited; start with -1.00 to -5.00 in 0.25 steps = ~17 pieces).
- Why this many? To test 1.50–2.00D reductions gradually (e.g., from your full -5.00, test -3.00, -3.25, etc., to find “just barely clear” for 0.4m phone use).
- For astigmatism, pair with cylinders below.
Total minimal spheres: 12–17 pieces (covers your range; a cheap kit has this).
Minimal Cylinders Needed (for Astigmatism Testing, Both Eyes)
Astigmatism is -1.00D, so test keeping it full or reducing slightly (e.g., to -0.75D) if it blurs close work.
- -0.25, -0.50, -0.75, -1.00, -1.25, -1.50 (6 powers).
- You need 2 of each (one for each eye), so 12 pieces total.
- Axes: Trial cylinders often have fixed axes (e.g., 90°, 180°); get a set with 4–6 common axes (e.g., 10°, 45°, 90°, 135°, 180°) to match your prescription. If your astigmatism axis is known (not in your data), prioritize it.
Total minimal cylinders: 12 pieces (or 6 if alternating eyes).
Grand Total Pieces Needed
- Minimal kit: 24 pieces (12 spheres + 12 cylinders) + a trial frame (~$20 extra). This lets you test 4–6 different under-correction combos per eye.
- If buying a full basic set: Look for a “student trial lens set” with 28–40 lenses (includes spheres -0.25 to -6.00, cylinders -0.25 to -2.00, and some plus powers). Cost: $60–150. Examples: “PUKITH Trial Lens Set” or similar on Amazon/eBay.
- How to use: Insert sphere + cylinder into the trial frame slots (one pair per eye). Start with full Rx, then reduce sphere by 0.25D increments. Test at phone distance (hold phone 30–50cm away): Adjust until it’s “just barely clear” (e.g., text readable but not sharp). Wear for 1–2 hours daily, building up.
- Don’t need prisms/adds yet: Unless you have convergence issues; your data doesn’t suggest it.
Suggested Prescriptions for Phone/Laptop (Under-Corrected Combos)
Using your full Rx as baseline, here are tested-friendly under-corrections for close work (aim: 1.50–2.00D sphere reduction). These make phone/laptop “just clear” at ~0.4m (using your formula: ~ -2.50D effective for slight blur at distance). Test with trial lenses to confirm—vision should be 0.8–1.0 at close range, blurry at 3m+.
For Phone (Closer, ~0.3–0.4m; More Reduction for Relaxation)
- Left Eye: Sphere -1.50D (2.00D reduction from -3.00) + Cylinder -1.00D. (Expected: Text clear but soft; distant blur encourages active focus.)
- Right Eye: Sphere -3.00D (2.00D reduction from -5.00) + Cylinder -1.00D.
- Pieces to assemble: 1 sphere + 1 cylinder per eye (4 total for both eyes).
For Laptop (Slightly Farther, ~0.5m; Less Reduction)
- Left Eye: Sphere -1.75D (1.25D reduction) + Cylinder -0.75D (slight astig. ease if needed).
- Right Eye: Sphere -3.50D (1.50D reduction) + Cylinder -0.75D.
- Pieces: Same as above (4 total). Swap cylinders if full -1.00D causes distortion up close.
Full Prescription for Driving/TV (Keep Separate)
- Left: -3.00D sph / -1.00D cyl.
- Right: -5.00D sph / -1.00D cyl.
- Pieces: 4 total (don’t under-correct for distance tasks).
Testing Tips for Your Experiment:
- Get a trial frame and start with 1–2 sessions/day (20–30 min) to adapt.
- Measure “clear distance” weekly: Hold a phone at arm’s length; note when it blurs (use your formula to track progress).
- If astigmatism blurs lines/text, reduce cylinder by 0.25D.
- Track like your table: Add columns for “Test Rx” and “Close Vision” (e.g., phone clarity 1–10 scale).
- Progress goal: Every 3 months, try 0.25D more reduction if close vision stays “just clear.”
- Buy from: Search “trial lens set myopia” on AliExpress/Amazon for affordable options. Ensure they have -0.25 increments.
If this doesn’t match what you meant or you have axis details, provide more info! Stay safe—eye health first.