Which data are needed when ordering SPORTS spectacle lenses?
The following parameters should be noted down when ordering for our SPORTS lenses:
- prescription (sphere, cylinder, axis, prism up to max. 2.5∆); for progressives we also need the "Add, SPORTS"
- PD, fitting height
- lens data (refractive index, base curve of the demo lens, diameter of the blank)
- frame data (lens size, distance between lenses (DBL), horizontal inclination of the frame)
Why is it necessary to check the horizontal inclination of the frame?
The horizontal inclination determines the angle between the frame plane and the fitted spectacle lenses. For general-wear frames this angle is smaller than for SPORTS frames. The horizontal inclination is required to optimise the lenses for SPORTS wear.
Why it is nessesary to measure the horizontal inclination with the frame in wear?
Sports glasses usually press against the temples. Deflection at the centre changes, depending on the size of the wearer's head. Thus, the horizontal inclination influences the measured power of the lenses.
How should I determine the diameter for SPORTS lens ordering? What parameters should I note down?
For the resulting diameter the frame PD and the wearer's PD must be taken into account.Note: Normally single vision lenses can be produced with additional prism for bigger diameters; with progressives this is not technically feasible.
Is there a lens tint which is specially recommended for sports?
The right choice of tint colour and absorption for wearer needs and ambient light conditions is crucial. It is a matter of subjective choice which tint and absorption feels best in wear. In general, the lighter the lenses the better.
Arancia plus Silver Shade is a versatile choice. Arancia Silver Shade is the combination of an orange tint and a graduated silver mirror finish with integrated back surface broadband AR coating.
How do I determine the base curve from the demo lens?
You can determine the base curve of demo lenses instrumentally or with our SPORTS measurement aid.
What types of frame are not suited to SPORTS glazing?
Types of frame not suited to SPORTS glazing are:
- Frames with toric groove configuration
- Injection moulded frames with rectangular, straight forms.
- Frames of a construction which only permits a specific lens thickness
- Bracket systems which only allow plano lenses
- Supra frames of base curve > 7.00 D
- Frames with a mini-V groove
- Metal frames without joint/ with joint which does not open.
Click here to find a list of suitable frames for SPORTS glazing.