Because the symptoms of sub-health we usually call are not obvious and will not affect life and work for the time being, the symptoms of sub-health are repeatedly ignored by everyone, and at the same time, they can not attract everyone’s attention. For your own health, it is particularly important to keep the symptoms of sub-health away from you and prevent sub-health.
Sitting posture will not cause hunchback, which not only affects beauty, but also causes uneven stress on spine joints and neck, shoulder, waist and back pain. Therefore, people should take countermeasures to prevent the occurrence of hunchbacks. The first countermeasure is to correct the bad posture in daily life and work, that is, to take the correct posture, the height of tables and chairs should be appropriate when sitting at the desk, and the upright posture must be maintained to avoid the flexion of neck, chest and waist.
But when reading, people have to look at the books or other objects on the table, that is, under the front, so that they have to lower their heads to make the cervical vertebrae in a forward bending position, which increases the burden of the cervical vertebrae. Over time, it is easy to make people hunchback or cervical vertebrae strain, and then suffer from cervical spondylosis. Even some people who wear ordinary glasses have their eyes too close to the book in order to achieve the best perspective when reading and writing. At this time, the lenses are almost parallel to the book, which makes the cervical vertebrae in an extremely flexed position and aggravates the strain of the cervical vertebrae.
If you want to keep the posture of sitting straight and physiological forward bending of cervical vertebra, the included angle between the lens and the temple should be 50 degrees, and the angle between the lens and the cheek should be 70 degrees, and the lower edge of the lens should be as close to the cheek as possible, so that the angle between the line of sight and the lens can be right angles for easy reading. In order to see the front and lower objects clearly, some people often pull down their glasses to the lower half of the nose or the tip of the nose to adjust the best angle of view.
However, there is no nasal bone in the lower part of the nose, only nasal cartilage, so one is uncomfortable, and the other is that the glasses flatten the nasal wing, affecting the smooth breathing. The angle between the lens and the temple should be different when moving different objects. For the above reasons, the angle between the glasses and the temple should be designed to be adjustable in elevation.
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