Adults 45+

    By the age of 45 the distance at which we see well close varies on a large “beach”, from 7cm to about 120 cm (depending on the size of the text used in the test), and in an adult over 45 years old this “beach” is in continuous decline, starting from 29cm and reaching over 100cm at the age of 60 years

~7cm ———————————-120cm at age 9 years

~ 29cm——————–120cm after 45 years — no glasses “up close”

~55cm———–120cm around the age of 50

~105cm——120cm at about 60 years old

∞ after 75 years

     So, the distance that we see well almost increases after 45 years, reaching infinity after 75 years, when the crystalline no longer has the accommodation.

     Due to the constant stiffening of the crystalline, after the age of 45, when the distance at which we see well almost begins to increase, the need for glasses for the correction of vision up close will arise.

     In this case, finding the optimal distance from the display is performed wearing the glasses recommended by the specialist.

     The distance at which we see well with the glasses up close will vary depending on the diopter of the glasses you will wear, and that “beach” in which we see well up-close will decrease in proportion to the age and stiffening of the crystalline, being more and more related to the formula D =m to the power of -1 (diopter is the inverse of the distance)

     In ideal conditions at 75, with +2.50 we see well up-close to 40cm. D=m to -1 (2.50=1:0.4)

     A person with myopia (small or large) will reach presbyopia (after 45 years) and will start gently, in time, to remove the glasses that he has worn relatively all his life at a distance and up-close (permanently), at the moment he wants to read or work in the up-close environment and eventually to get extremely close to the object being watched (excluded astigmatisms). Presbyopia manifests itself in reverse in an emetrope (person without dioptric needs) or in a person with hyperopia (positive dioptric need).

     When the lens is clouded due to the appearance of cataracts, the person in question (usually over 60 years old) begins to see very well in the up-close environment, much better than younger relatives by 10-15 years, but gradually begins to lose sight at a distance (due to the advancement of cataracts, and in the end, also loses up-close vision). The lens is opaque due to cataract and induces a negative dioptric value, that masks the presbyopia (the need for addition in the up-close environment). This is the myth known as “vision returns at a certain age.”

     The only cause of the appearance of early cataracts (but not traumatic), up to 75-80 years (when it occurs physiologically but not necessarily in any person), is the incorrect wearing of the up-close glasses.

    Consulting the table of accommodation of the crystalline (from Kids and Adults) and finding that they are in a major regression after the age of 45 and adding the experience gained as most people in this case do not give much importance to the way of wearing the up-close glasses, it resulted that a large part of those who reached the presbytery, they are making a mistake by looking through the up-close glasses to far away distances (one second a day is enough), thus getting to wear distance glasses as well. This daily repeated mistake forces the crystalline to accept a distant dioptric deformation during their period of natural regression. So, it forces the appearance of clouding of the lens, that is, cataracts. In this case, the fact that people over 50 mostly refuse to wear distance glasses or especially sunglasses (with or without dioptric correction) also helps, as they help crystalline a lot during this period of life.        

Natural crystalline can work properly all our lives if we pay attention to wear up-close glasses and sunglasses !

Progressive lenses

    Progressive glasses are used after the age of 45-50, when the difference between the diopter from a distance (0 if we do not have problems) and the up-close one is more than a diopter (the personal recommendation is after the difference exceeds 1.5 dpt, because up to this level the crystalline has some flexibility and still helps).

    From the name of the (progressive) lenses we deduce that it is a dioptric progression between the diopter of distance and the near-up. If we have 0 at a distance and +1.50 close, then the lenses will have a step progression of 0.25 dpt. from 0 to +1.50. Due to this v-man progression we have improved vision at different distances because the diopter is directly related to the distance at which we want to look (D=m at the power -1).

    In principle, the progressive lens will also help us to see well at intermediate distances (approximately between 40 cm and 1.0m), not just up-close or at a distance (bifocal lens). However, these lenses are not recommended in the office, if we are working on the desktop, since the position of the head to see well at the intermediate distance is not correct. In this case, degressive lenses are the solution, lenses that have a progression only for up-close and intermediate distances. If in the office we use a laptop, then the situation changes, and progressive glasses can also be worn in certain cases.