Loaʻa nā hoʻokolohua like ʻole e ʻike ai i ka makapō kala, kahi kīnā ʻike e pili ana i ka ʻokoʻa kala, a pili i ka 8% o ka heluna kāne i ka 0,45% wale nō o nā wahine. ʻO ka mea kaulana loa o kēia mau hoʻokolohua ʻo ia ʻo Ishihara.

ʻO ka makapō kala (i kapa ʻia ma hope o ka 18th century English physicist John Dalton) he kīnā ʻike e pili ana i ka ʻike o nā kala. He maʻi genetic ia: ma muli o kahi anomaly (ka ʻole a i ʻole ka hoʻololi ʻana) i loko o nā genes e hoʻopili ana i nā puaʻa ʻulaʻula a me ka ʻōmaʻomaʻo, aia ma ka X chromosome, a i ʻole ma nā genes encoding blue, ma ka chromosome 7 No laila he hereditary ka makapō kala. no ka mea, hiki i kekahi a i ʻole nā ​​mākua ʻelua ke hele i kēia hemahema genetic. He mea maʻamau ia i nā kāne no ka mea, lawe lākou i ʻelua X chromosomes. ʻOi aku ka kakaikahi, hiki i ka makapō waihoʻoluʻu ke lilo i ka lua o ka maʻi maka a i ʻole ka maʻi maʻamau (diabetes).

Ma muli o ke ano o ka genetic abnormality, aia nā ʻano like ʻole o ka makapō kala:

Monochromatism (a i ʻole achromatism): ʻaʻole ʻokoʻa ke kanaka i kekahi kala a no laila ʻike wale ʻo ia i ka ʻeleʻele, keʻokeʻo a me nā aka hina. He kakaikahi loa keia anomaly.

ʻO ka dichromie : kekahi o nā genes, a no laila ʻaʻole i loaʻa kekahi o nā puaʻa.

• inā ʻo ka gene e hoʻopili ana i ka ʻulaʻula, he protanopic ke kanaka: ʻike wale ʻo ia i ka uliuli a me ka ʻōmaʻomaʻo;
• inā ʻo ka gene e hoʻopili ana i ka ʻōmaʻomaʻo, he deuteranopic ke kanaka: ʻike wale ʻo ia i ka uliuli a me ka ʻōmaʻomaʻo;
• inā ʻo ia ka gene coding no ka uliuli, he tritanopic ke kanaka: ʻike wale ʻo ia i ka ʻulaʻula a me ka ʻōmaʻomaʻo.

ʻO ka trichomatie maʻamau : hoʻololi ʻia kekahi o nā genes, no laila ua hoʻololi ʻia ka ʻike o ke kala.

• inā ʻo ia ka gene e hoʻopili ana i ka ʻulaʻula, he protanormal ke kanaka: pilikia lākou i ka ʻike ʻulaʻula;
• inā ʻo ia ka gene coding no ka ʻōmaʻomaʻo, he deuteranormal ke kanaka: pilikia lākou i ka ʻike ʻana i ka ʻōmaʻomaʻo;
• inā ʻo ia ka gene coding no ka uliuli, he tritanormal ke kanaka: paʻakikī ko lākou ʻike ʻana i ka uliuli.

No ka ʻike ʻana i kēia mau anomalies, aia nā hoʻokolohua like ʻole. Eia nā mea nui:

• e hoao i ka Ishihara, i kapa ʻia ma hope o kāna mea hana Kepani ʻo Shinobu Ishihara (1879-1963), ʻo ia ka mea i hoʻohana pinepine ʻia. Hiki iā ia ke ʻike i nā hemahema ʻulaʻula a me ka ʻōmaʻomaʻo (protanopia, protanomaly, deuteranopia, deuteranomaly). Hele mai ia ma ke ʻano o 38 mau papa pseudo-isochromatic: i loko o ka pōʻai he mau kiko o nā ʻano nui a me nā kala, kahi e kū ai, no ka mea i ʻike maʻamau (trichomate), kahi helu. Hōʻike ʻia kēia mau papa i kahi kauoha pololei i ka mea maʻi, pono e ʻōlelo i ka helu āna i hoʻokaʻawale ai a ʻaʻole paha.
• le ho'āʻo "ʻike kala i maʻalahi" ʻo ia ka mana o nā keiki o ka hoʻāʻo pseudo-isochromatic. Ma kahi o nā kiʻi, he mau ʻano kēia i hiki ke ʻike ʻia ma nā papa.
• les ho'āʻo Panel D15 a me Farnsworth-Munsell ʻO 100-hue, i hoʻomohala ʻia e Dean Farnsworth i ka makahiki 1943, hele mai ma ke ʻano o nā kiko liʻiliʻi liʻiliʻi e kau ʻia i ka hoʻonohonoho pololei.
• ʻO nā hoʻokolohua Holmgren hoʻohana i nā ʻili huluhulu kala. ʻEkolu o ia mau mea he kuhikuhi: skein A no ka ʻōmaʻomaʻo, B no ka poni a me C no ka ʻulaʻula. Pono ka mea maʻi e koho ma waena o 40 mau skeins ʻē aʻe 10 e pili kokoke ana i ka waihoʻoluʻu A, 5 i ka waihoʻoluʻu B a laila 5 i ka C. A laila pono ʻo ia e hoʻokaʻawale iā lākou ma ke kala kala. Hoʻohana nui ʻia kēia hoʻāʻo no ka ʻike ʻana i ka makapō kala i nā luina, nā limahana hana kaʻaahi a me nā airmen, pāpā ʻia nā ʻoihana no ka poʻe makapō kala ma muli o ka hoʻohana ʻana i nā hōʻailona ʻulaʻula a me ka ʻōmaʻomaʻo.
• ka hoao Verriest, i hana ʻia i ka makahiki 1981, no nā keiki. hele mai ia ma ke ʻano o nā hōʻailona kala e ʻākoakoa ai, e like me ka domino.
• e hoao i ka Pease a me Allen (1988) no na keiki. Hele mai ia ma ke ʻano o 4 mau ʻāpana kala (keʻokeʻo, ʻulaʻula, ʻōmaʻomaʻo a me ka uliuli) me kahi ʻāpana liʻiliʻi o ke kala ʻokoʻa ma kahi kihi, ma ka piko o ka ʻāpana. Pono ke keiki e ʻike i nā kala.

Hana ʻia kēia mau hoʻāʻo i ka wā e kānalua ai ka makapō kala, i nā "ʻohana" o ka poʻe makapō kala a i ʻole ke kiʻi ʻana no kekahi mau ʻoihana (ʻoi aku ka hana o ka halihali lehulehu).

ʻAʻohe lāʻau lapaʻau no ka makapō kala, ʻaʻole i ʻoi aku ka ʻino a i ʻole ka hoʻomaikaʻi ʻana i nā makahiki. A ʻo ka poʻe me ka makapō waihoʻoluʻu maʻamau e launa pū me kēia ʻano ʻano liʻiliʻi.

Aia nō, ʻoiaʻiʻo, nā aniani, a me nā lens kūikawā, loaʻa nā kānana kala e hoʻololi i ka spectrum kala, akā hoʻohana liʻiliʻi lākou.