An eye is corrected by a -5.50D lens, 2.0 cm from theeye. (a) Is this eye near- or farsighted? (b) What is thiseye’s far point without glasses?

A far-sighted person has a near point of 1.75 m. What is the refracting power of contact lensesthat would correct their vision, resulting in a near point of 0.25 m?

A compound microscope is made from an objective lens of focal length fo = 8 mm, andan eyepiece of fe = 12 mm. The objective lens is moved close to the object so that anintermediate image is formed 20 cm above the objective lens; then the eyepiece is set atits own focal length above the intermediate image, forming a virtual image at infinity forthe user’s eye. If the object is 0.15 mm in diameter, calculate the following, taking care todefine symbols used:i) The required distance of the objective lens above the object.ii) The diameter of the intermediate image.iii) The angular size of the image to the user’s eye.iv) The system angular magnification, defined as the angular size in (iii) divided by theangle subtended by the object to the naked eye from a distance of 25 cm.

A nearsighted man wears contact lenses of -3.00 diopters. With these lenses, his corrected near point is 25.0 cm. What is his uncorrected near point?

A person uses corrective glasses of power -8.5 D.  (a) Is this person nearsighted or farsighted?  (b) If the glasses are worn 2.0 cm from the eye, what is the person's far point without glasses?