Eyeglass prescription (Wikipedia)
- DV is an abbreviation for distance vision（遠視力、遠見、遠用視力）. This specifies the part of the prescription designed primarily to improve far vision（遠方視力）. In a bifocal lens, this generally indicates what is to be placed in the top segment.
- NV is an abbreviation for near vision（近見視力）. This may represent a single-vision lens prescription to improve near work, or the reading（近用）portion of a bifocal lens. Some prescription forms use ADD in place of NV with a single box to indicate the additional refractive power（屈折力）to be added to the spherical power（球面度数）of each eye.
- OD is an abbreviation for oculus dexter, Latin for right eye from the patient's point of view. Oculus means eye.
- OS is an abbreviation for oculus sinister, Latin for left eye from the patient's point of view.
- OU is an abbreviation for oculi uterque, Latin for both eyes.
N.B.: In some countries, such as the United Kingdom RE (right eye), LE (left eye), and BE (both eyes) are used. Sometimes, just right and left are used.
- SPH is an abbreviation for spherical correction. This corrects refractive error of the eye with a single convergent or divergent refractive power in all meridians（経線）.
- CYL is an abbreviation for cylindrical correction. This corrects astigmatic（乱視）refractive error of the eye by adding or subtracting power（度数）cylindrically in a meridian specified by the prescribed axis.
- AXIS is present only if there is a value for CYL. This indicates the angle in degrees of one of two major meridians the prescribed cylindrical power is in. Which major meridian is referenced is indicated by the cylindrical correction being in plus or minus notation. The axis is measured on an imaginary semicircle with a horizontal baseline that starts with zero degrees in the 3 o'clock direction (as viewed by the person making the measurement), and increases to 180 degrees in a counter-clockwise direction.
- ADD is an abbreviation for Near（近用）Addition. This is the additional correction required for reading.
Most eyeglass prescriptions will contain values here. The spherical and cylindrical columns contain lens powers in diopters（ディオプトリ、ジオプトリ、視度）(see below).
Prism and Base are usually left empty, as they are not seen in most prescriptions. Prism refers to a displacement （位置ずれ）of the image through the lens, and is used to treat eye muscle imbalances or other conditions (see vergence dysfunction) that cause errors in eye orientation or fixation（固視）. Prism correction is measured in prism diopters, and Base refers to the direction of displacement.
- Pupillary Distance（瞳孔間距離）(PD) is the distance between pupil centers, usually expressed in millimeters. It is sometimes known as the interpupillary Distance（瞳孔間距離）(IPD). It is written as two values if the prescription is for bifocals or progressive lenses - these are the pupillary distances for the distance（遠用）and near（近用）fixation (essentially, the upper and lower part of the lenses). They differ due to pupillary convergence when looking at near objects. Additionally, an eyeglasses prescription may include a monocular pupillary distance ("monocular PD"). These measurements indicate, in millimeters, the distances from the center of each pupil to the center of the nose where the center of the frame bridge rests. PD measurements are essential for all spectacle（眼鏡）dispensings（処方？）, monocular PDs being essential in progressive lenses and for those with high prescription. PDs can be measured using a pupilometer or by using a ruler. In some countries, such as the United Kingdom, PD measurement is not a legal requirement as part of the prescription and is often not included."
Dioptre (Wikipedia)
The fact that optical powers（屈折力？）are approximately additive enables an eye care professional to prescribe（処方）corrective（補正、矯正）lenses as a simple correction to the eye's optical power, rather than doing a detailed analysis of the entire optical system (the eye and the lens). Optical power can also be used to adjust a basic prescription for reading（近用、読書用）. Thus an eye care professional, having determined that a myopic (nearsighted) person requires a basic correction of, say, −2 dioptres（ディオプトリ、ジオプトリ）to restore normal distance vision（遠用、遠見視力）, might then make a further prescription of 'add 1' for reading, to make up for lack of accommodation（調節） (ability to alter focus). This is the same as saying that −1 dioptre lenses are prescribed for reading."
US9411173
(Abstract)
"A spectacle（眼鏡）lens is disclosed. The disclosed lens provides a vision correcting area for the correction of a wearer's refractive error. The viewing correction area provides correction for non-conventional refractive error to provide at least a part of the wearer's vision correction. The lens has a prescription based on a wave front analysis of the wearer's eye and the lens can further be modified to fit within an eyeglass frame."
"When the electro-active layer is activated, its index changes, and the refractive power of the diffraction pattern becomes additive to the substrate lens. For example, if the substrate lens has a power of −3.50 diopter（ジオプトリ）, and the electro-active diffractive layer has a power when activated of +2.00 diopter, the total power of the electro-active lens assembly is −1.50 diopter. In this way, the electro-active lens allows for near vision（近用）or reading. In other embodiments, the electro-active layer in the activated state may be index matched to the lens optic."
"In many cases, the wearer will require spherical correction for distance（遠用）, near, and/or intermediate vision."
US6199984
"The use of ophthalmic lenses for the correction of ametropia is well known. For example, multifocal lenses, such as progressive addition lenses (“PALs”), are used for the treatment of presbyopia. Typically, a PAL provides distance（遠用）, intermediate, and near（近用）vision zones in a gradual, continuous progression of increasing dioptric power. PALs are appealing to the wearer because the lenses are free of the visible ledges between the zones of differing optical power that are found in other types of multifocal lenses, such as bifocals and trifocals."
