Question 9 (2 points) What are the two factors that determine the strength of a lens? A/ Question 10 (1 point) What information do 'diopters' provide? A/Question 7 (2 points) How does a 'minus' lens alter the path of light rays as they move through it? How does this move the eye's focal point? A/ Question 8 (2 points) How does a 'plus' lens alter the path of light rays as they move through it? How does this move the eye's focal point?Question 1 {2 points] What is the retina? Where in the eye is it located? Question 2 {3 points] What are three things that must happen to an image befere you can see it? Light passing through a lens is always bent toward the thickest edge. To make a minus lens the thickest parts are the outer edges and the thinnest part is in the middle. This spreads the light away from the cerrtre of the lens and moves the focal point further back. The stronger the lens. the farther the focal point is from the lens. People with myopia rely on minus lenses to bring their focal point back so what they see can be focussed on their retina. E \"11 ' In .G "acted \"II b H20 To make a plus lens the thickest part is the middle and the yaw mynpi P1 0 m an\" a m] thinnest parts are the outer edges. The light is bent toward the centre and the focal point moves forward. The stronger the lens, the closer the focal point is to the lens. People with hyperopia rely on minus lenses to bring their focal point forward so what they see can be focussed on their retina. Placing the correct type and power of lens in front of the eye will adjust the focal point to compensate for the eye's inability to focus the image on the retina. Determining Lens Strength The strength of a lens is determined by the lens material and the angle of the curve that is ground into the lens. Lens strength is memmg expressed as diopters {D}. which indicates howr much the light is "m" m bent. The higher the diopter. the stronger the lens. Also, a plus [+1 or minus H sign before the diopter strength indicates the Eyn I.uIitlI hyporopinttnp]. Corrected will! Inns {bottom} type oflens.