Rudy Project Rydon Optical Dock with High-Prescription ZEISS Lenses

 

Rudy Project Rydon Optical Dock with High-Prescription Lenses

A customer traveled from Jincheon, Chungcheongbuk-do, to Eyedaq Optical in Myeongdong to have prescription lenses fitted into a Rudy Project Rydon.

Because the prescription was relatively strong, we selected the Rydon Optical Dock. This full-rim prescription system is particularly suitable for high-myopia lenses because it provides secure lens mounting while helping conceal visible edge thickness.

Prescription
Right eye: -6.50D sphere / -0.25D cylinder
Left eye: -5.50D sphere / -0.75D cylinder

Lens: ZEISS Single Vision Superb 1.67
Lens color: Gray tint
Finish: Silver half-mirror coating

Why We Chose the Rydon Optical Dock

There are several ways to add prescription correction to Rudy Project sports eyewear. A small optical insert can be mounted behind the original sports lenses, but this creates a two-layer structure.

The Optical Dock uses a different approach. It replaces the standard lens section with a full-rim prescription module, allowing the prescription lenses to provide the wearer’s direct field of vision.

This structure is especially useful for stronger prescriptions. Minus lenses are thin in the center and become thicker toward the edges. The Optical Dock keeps the prescription lens area relatively compact, while its full-rim design helps cover and securely hold the thicker lens edges.

However, the Optical Dock does not guarantee a thin result for every prescription. Monocular pupillary distance, lens shape, optical-center decentration, astigmatism, and the wearer’s actual fitting position must all be checked before production.

ZEISS Single Vision Superb 1.67 Lenses

For this pair, we used ZEISS Single Vision Superb lenses in a 1.67 high-index material.
The 1.67 material is suitable for moderately high and high-myopia prescriptions because it can reduce edge thickness compared with lower-index lens materials under similar conditions.

Lens thickness is not determined by refractive index alone. Frame size, lens shape, optical-center position, minimum center thickness, and edging method also influence the final result. For this reason, the frame and lenses must be considered as one complete system.

Gray Tint with Silver Half-Mirror Coating
A gray tint was selected for comfortable outdoor use. Gray lenses provide a natural visual tone without strongly emphasizing a particular color, making them suitable for cycling, running, trekking, and everyday outdoor activities.

A silver half-mirror coating was added to create a sportier appearance and reduce the visibility of the wearer’s eyes from the outside. It also matches the black and silver details of the Rydon frame.

A mirror coating is different from polarization. Customers who specifically want to reduce reflected glare from roads or water should consider polarized lenses separately.

Curved Sports Eyewear Requires Careful Prescription Testing

The Rudy Project Rydon has a more pronounced wrap angle than ordinary eyeglass frames. When lenses are positioned at an angle around the face, the wearer may experience vision differently from a flat everyday frame.

For people with high myopia, even a small change in lens position can affect peripheral vision, spatial perception, and adaptation. Simply transferring the everyday eyeglass prescription without checking the sports-frame conditions may cause discomfort.

At Eyedaq Optical, we use a curved trial frame to evaluate the prescription under conditions similar to wraparound sports eyewear. This helps us check visual comfort and determine whether any prescription adjustment is necessary before ordering the lenses.

Measuring the Optical Centers with ZEISS VISUFIT 1000

After adjusting the nosepiece and temples, we measure the optical-center positions in the customer’s actual wearing posture.

ZEISS VISUFIT 1000 is used to measure monocular pupillary distance, fitting height, and other frame-position data. It does not determine the prescription itself. Its role is to position the confirmed prescription accurately within the lenses according to how the frame sits on the wearer’s face.

This process is particularly important for high-prescription sports eyewear, where small centration errors can become more noticeable.

Final Fitting Is Part of the Process

After the lenses are installed, the nosepiece and temples must be adjusted again. The frame should remain stable during movement without creating excessive pressure on the nose, ears, or temples.

Prescription lenses can be heavier than standard non-prescription sports lenses, so balanced fitting is essential. For cyclists, it is also helpful to check how the temples interact with a helmet and helmet straps.

This Rudy Project Rydon was completed with an Optical Dock, ZEISS Single Vision Superb 1.67 lenses, a gray tint, and a silver half-mirror finish.

Successful prescription sports eyewear requires more than simply inserting lenses into a frame. Prescription testing under curved conditions, accurate optical-center measurements, careful edging, and final fitting must all work together to provide stable and comfortable vision during sports activities.

#RudyProjectRydon #RydonOpticalDock #PrescriptionSportsGlasses #HighMyopiaGlasses #ZEISSSuperb #CurvedSportsEyewear #EyedaqOptical

Naito Kumahachi Saku N-401: A Compact Frame for Strong Myopia Prescriptions

 

-9.50D High-Myopia Glasses: A Small Frame Paired with 1.74 Double-Aspheric Lenses

High-myopia glasses do not automatically become thin and comfortable simply by choosing a high-index lens. The size and shape of the frame, the wearer’s pupillary distance, optical center position, bevel placement, and final fitting must all be considered together.

This pair was made for a high-myopia prescription with astigmatism.

Prescription

Right eye: Sphere -9.50D / Cylinder -1.50D
Left eye: Sphere -9.00D / Cylinder -1.00D
Lens: 1.74 high-index double-aspheric lens

The cylinder axes were not included in the provided prescription, so they are not listed here.

Naito Kumahachi Saku N-401 Eyeglass Frame

The inner surface of one temple is engraved with “908 內藤熊八作 since 1976 N-401.” The opposite temple is marked “MADE IN JAPAN 44□21-145 Titanium.”

The frame is the N-401 model by the Japanese eyewear brand Naito Kumahachi Saku. According to the manufacturer’s specifications, it is a full-rim combination frame with an acetate front and titanium temples. Its size is 44□21-145, and the color shown in the photographs is C-1 Black/Gold. The frame is officially categorized as a square shape.

In person, the N-401 appears more like a softly rounded, compact square frame than a sharply angular design. The keyhole bridge and black acetate front create a vintage impression, while the gold-colored titanium temples and end pieces feature finely engraved decorative patterns.

From a distance, the frame looks neat and understated. Up close, its detailed craftsmanship becomes more noticeable. This balance reflects the brand’s distinctive combination of vintage styling and refined geometric decoration.

Why the Small Lens Size Is Advantageous for High Myopia

The N-401 has a lens width of 44 mm, which is relatively compact for a high-myopia frame. Its rounded corners also prevent the lens shape from extending too far outward, helping reduce visible edge thickness.

A minus lens is thinnest at the center and becomes progressively thicker toward the edges. When the frame is smaller, the distance between the optical center and the outer edge of the lens is reduced. This can help lower both the final lens thickness and overall weight.

However, a small lens width does not guarantee a thin result for every wearer. The N-401 has a lens width of 44 mm and a bridge width of 21 mm, giving it a frame PD of approximately 65 mm.

When the wearer’s pupillary distance is significantly narrower than 65 mm, the optical centers must be decentered inward. As the amount of decentration increases, the outer edges of the lenses may become thicker. For this reason, frame size should always be evaluated together with monocular PD measurements and the wearer’s actual optical center positions.

Advantages of a Black Full-Rim Frame

With high-myopia lenses, the thick outer edges can be noticeable from the front and sides. A dark black acetate full-rim frame surrounds the lenses and helps conceal their thickness more effectively than a transparent frame or a thin metal design.

The moderately thick acetate front also covers part of the lens edge, creating a cleaner overall appearance. In high-myopia eyewear, it is important not only to reduce the actual thickness but also to choose a frame that makes the remaining thickness less visible.

Why 1.74 Double-Aspheric Lenses Were Selected

This pair was fitted with 1.74 high-index double-aspheric lenses. A 1.74 material is classified as an ultra-high-index plastic lens material. Under the same prescription and frame conditions, it can generally produce a thinner lens than a lower-index material.

Double-aspheric lenses use aspheric designs on both the front and back surfaces. They are commonly selected for strong prescriptions to improve peripheral optics and create a flatter, more natural-looking lens profile than conventional spherical lenses.

Actual thickness and visual performance can still vary depending on the lens manufacturer, individual lens design, frame shape, optical center position, and edging conditions.

It is also important to understand that a 1.74 lens does not always produce the lightest possible pair of glasses. Final weight and thickness are affected by the prescription, lens shape, frame size, amount of decentration, minimum center thickness, and edging method.

Important Points When Making High-Myopia Glasses

Accurate monocular PD and fitting-height measurements are essential. The stronger the prescription, the more noticeable even a small optical-center error can become. Measuring each eye individually is therefore preferable to relying only on the total binocular PD.

Bevel placement must also be carefully determined during the edging process. If the bevel is positioned too far toward the front or back surface, the lens may protrude excessively from one side of the frame. By considering the thickest part of the lens and the position of the frame groove, the lens thickness can be distributed more naturally toward the inner side of the frame.

Final fitting is equally important. The height and angle of the nose pads, temple spread, pantoscopic tilt, and vertex distance should all be adjusted to suit the wearer.

High-myopia lenses may carry additional weight around their outer edges. The nose pads and temples must therefore be balanced carefully to prevent the glasses from sliding forward or sitting unevenly.

Who Is the N-401 Best Suited For?

The Naito Kumahachi Saku N-401 is well suited to people with small or relatively narrow faces, as well as those looking for a compact frame for a high-myopia prescription.

The black-and-gold combination looks classic without appearing overly heavy. It creates a neat, professional impression with business attire and adds a vintage accent to more casual clothing.

The design is suitable for both men and women. However, because the overall width is compact, wearers with broader faces should check for pressure around the temples and excessive outward spreading of the temple arms.

This pair is a good example of how a compact lens shape, a black acetate full-rim front, adjustable nose pads, and 1.74 double-aspheric lenses can be combined for a strong high-myopia prescription.

The quality of high-myopia glasses is not determined by the lens index alone. A suitable frame, precise optical measurements, careful edging, and detailed final fitting must work together to create glasses that look more natural and remain comfortable throughout the day.

#HighMyopiaGlasses #NaitoKumahachiSaku #N401Eyewear #DoubleAsphericLenses #JapaneseEyewear #HighIndexLenses #EyedaqOptical