22/04/29ʻO ka Photo-response Non-uniformity (PRNU) he hōʻike ia o ke kūlike o ka pane ʻana o ke kāmela i ka mālamalama, mea nui i kekahi mau noi kukui kiʻekiʻe.
Ke ʻike ʻia ka mālamalama e ka pahupaʻikiʻi, e ana ʻia ka helu o nā kiʻi-electrons i hopu ʻia e kēlā me kēia pika i ka wā o ka hoʻolaha ʻana, a hōʻike ʻia i ke kamepiula ma ke ʻano he helu kikohoʻe hina (ADU). ʻO kēia hoʻololi ʻana mai nā electrons i nā ADU e hahai ana i kahi ratio o ADU no kēlā me kēia electron i kapa ʻia ʻo ka hoʻololi ʻana, me kahi waiwai offset paʻa (maʻamau 100 ADU). Hoʻoholo ʻia kēia mau waiwai e ka Analogue-to-digital converter a me Amplifier i hoʻohana ʻia no ka hoʻololi ʻana. Loaʻa i nā kāmeʻa CMOS ko lākou wikiwiki a me nā hiʻohiʻona haʻahaʻa haʻahaʻa ma o ka hana like ʻana, me hoʻokahi a ʻoi aku paha nā mea hoʻololi analogue-to-digital ma kēlā me kēia kolamu o ke kāmela, a me hoʻokahi amplifier no ka pika. Hoʻokomo ʻia kēia i kahi manawa no nā ʻano liʻiliʻi o ka loaʻa a me ka offset mai ka pixel a i ka pixel.
Hiki i nā ʻokoʻa o kēia waiwai offset ke alakaʻi i ka walaʻau kumu paʻa ma ke kukui haʻahaʻa, i hōʻike ʻia e kaDSNU. Hōʻike ka PRNU i nā ʻano like ʻole o ka loaʻa, ka lakio o nā electrons i ʻike ʻia i hōʻike ʻia ADU. Hōʻike ia i ka ʻokoʻa maʻamau o nā waiwai loaʻa o nā pika. Ma muli o ka hopena o ka ʻokoʻa i nā waiwai ikaika e pili ana i ka nui o nā hōʻailona, ua hōʻike ʻia ma ke ʻano he pakeneka.
ʻO nā waiwai PRNU maʻamau he <1%. No nā kiʻi haʻahaʻa haʻahaʻa a me ke kukui uila, me nā hōʻailona o 1000e- a i ʻole ka liʻiliʻi, ʻaʻole nui kēia ʻano hoʻololi i ka heluhelu ʻana i ka walaʻau a me nā kumu leo ʻē aʻe.
A i ke kiʻi ʻana i nā pae kukui kiʻekiʻe, ʻaʻole paha he mea nui ka hoʻololi ʻana i ka hoʻohālikelike ʻia me nā kumu walaʻau ʻē aʻe o ke kiʻi, e like me ka leo kiʻi photon. Akā, i nā noi kiʻi kiʻi kiʻekiʻe e koi ana i ka pololei ana kiʻekiʻe, ʻoi aku ka poʻe e hoʻohana ana i ka frame-averaging a i ʻole ka hoʻohālikelike ʻana i ke kiʻi, pono paha ka PRNU haʻahaʻa.
