Ka taea te whakatika i te tirohanga tata me te tirohanga tawhiti mā te whakamahi i ngā karāhe mōhiti me ngā karāhe whakapā . Ka piri ngā karāhe mōhiti ki ngā karāhe, ko ngā karāhe whakapā ia ka piri ki te pupil o te kanohi. Kei tētahi tawhiti motuhake ngā karāhe mai i te kanohi, ko ngā karāhe whakapā ia ka piri ki te kanohi, nō reira he iti noa te tawhiti i waenganui i te karāhe whakapā me te kanohi.
E whakamārama ana tēnei tuhinga i ngā tauira o ngā raruraru e pā ana ki te hunga kite tata me te hunga kite tawhiti, ngā momo karaihe e whakamahia ana hei whakatika i te tirohanga, ō rātou roa arotahi, me ō rātou kaha. E arotahi ana tēnei tuhinga ki te whakamahinga o ngā mōhiti hei whakatika i ngā kanohi kite tata me te hunga kite tawhiti.
Te Tirohanga Tata me ngā Arotahi Kōpiko
Te pūwāhi tawhiti Ko te kanohi kite tata, ko te kanohi pōuri rānei, he 102 cm te whānui. Kia mārama ai te tirohanga a te kanohi kite tata ki ngā mea i te mutunga kore, whakatauhia (a) te momo karāhe arotahi e whakamahia ana, (b) te roa o te arotahi o te karāhe arotahi, (c) te kaha, te mana rānei o te karāhe arotahi.
Ko te tikanga, e 2 henemita te tawhiti o ngā karāhe karaihe mai i ngā kanohi.
Kōrero
(a) Momo karaihe i whakamahia
Mō te kaupapa te tirohanga tata Kua whakamāramahia ko ngā karāhe arotahi e whakamahia ana hei whakataurite i te tirohanga tata o ngā kanohi ko ngā karāhe arotahi kōpiko, ko ngā karāhe arotahi wehewehe, ko ngā karāhe arotahi kino rānei.
(B) Roa arotahi o te arotahi
Kia kore ai e mutu te tawhiti o tētahi mea e tirohia ana e te kanohi tata mā te karu tirohanga, me hanga e te karu tirohanga he ahua i te tawhiti o te 102 cm ki mua i te kanohi, koinei te pito tawhiti o te kanohi tata. E 2 cm te tawhiti o te karu tirohanga mai i te kanohi, nō reira e 100 cm te ahua ki mua i te karu tirohanga. Kei mua te ahua i te karu tirohanga, nō reira he mariko, he poutū te ahua (whakatairitehia te whakamārama i roto i te kaupapa whakaahua karaihe kōpiko)
E mōhiotia ana :
Te tawhiti o te mea (s) = te mutunga kore
Te tawhiti o te ahua (s') = -100 cm (kino nā te mea he mariko te ahua)
I pātaihia Roa (f)
Whakautu :
1/h = 1/h + 1/h'
1/f = 1/~ + (- 1/100)
1/f = 0 – 1/100
1/f = – 1/100
f = – 100/1 henimita = -100 henimita = -1 mita.
Ko te roa arotahi kino ko te arotahi e whakamahia ana he karāhe kōpiko ranei arotahi wehewehe.
(c) Mana arotahi
P = 1/f = 1/-1 m = -1 Dioptera
Ko te kaha, te mana rānei o te arotahi he -1 D. Ko te tohu kino he tikanga ko te arotahi e whakamahia ana he arotahi kōpiko, he arotahi wehewehe rānei.
Te Tirohanga Tata me ngā Arotahi Pūpū
Ko te pūwāhi tata o te kanohi o te tangata e kite tata ana he 102 cm. Kia taea ai e te tangata te pānui i te tawhiti o te 25 cm i mua i te kanohi, whakatauhia (a) te momo karāhe arotahi i whakamahia, (b) te roa o te arotahi o te karāhe arotahi, (c) te kaha o te karāhe arotahi.
Ko te tikanga, e 2 henemita te tawhiti o ngā karāhe karaihe mai i ngā kanohi.
Kōrero
(a) Momo karaihe i whakamahia
Mō te kaupapa tirohanga tawhiti Kua whakamāramahia ko ngā karāhe arotahi e whakamahia ana hei whakataurite i te tirohanga tata ko ngā karāhe arotahi pūkohu, ngā karāhe arotahi whāiti rānei, ngā karāhe arotahi pai rānei.
(B) Roa arotahi o te arotahi
Kia 25 cm te tawhiti o te tirohanga o tētahi mea ki mua i te kanohi, me hanga e te arotahi he ahua i te tawhiti o te 102 cm, koinei te pūwāhi tata o te kanohi e kite tata ana. E 2 cm te tawhiti o te arotahi mō ngā karu mai i te kanohi, nō reira me 100 cm te tawhiti o te ahua ki mua i te arotahi, ā, me 23 cm te tawhiti o te mea ki mua i te arotahi. Kei mua i te arotahi te ahua, nō reira he poutū, he mariko te ahua (whakatairitehia te whakamārama i roto i te kaupapa whakaahua karaihe kōpiko)
E mōhiotia ana :
Te tawhiti o te mea (s) = 23 cm
Te tawhiti o te ahua (s') = -100 cm (kino nā te mea he mariko)
I pātaihia Roanga arotahi (f)
Whakautu :
1/h = 1/h + 1/h'
1/f = 1/23 + 1/-100
1/f = 1/23 – 1/100
1/f = 100/2300 – 23/2300
1/f = 77/2300
f = 2300/77 = 30 cm = 0,3 mita
Ko te roa arotahi pai ko te arotahi e whakamahia ana he arotahi pūkohu, he arotahi hūpeke rānei, he arotahi pai rānei.
(c) Mana arotahi
P = 1/f = 1/0,3 = +3 Ngā Diopter
Ko te kaha, te mana rānei o te arotahi he +3 D. Ko te tohu pai ko te arotahi e whakamahia ana he karāhe kōpiko, karāhe hūpeke rānei.
