Dị ka X-ray akpa-arụ ọrụ?

X-ụzarị na- eme site n'ịtụgharị ume nke electrons ka photons, nke pụtara na X-ray tube. Ibu (ikpughe) na àgwà (ụdịdị dị iche iche) radieshon nwere ike gbanwere agbanwe na nke ugbu a, voltaji na oge nke na ngwá.

ụkpụrụ nke ime ihe

X-ray akpa (foto nyere ke ibuotikọ) bụ ike converters. Ha na-enweta ya site na netwọk na converted n'ime ọzọ forms - abami radieshon na okpomọkụ, na nke ikpeazụ bụ ihe ekwesighi byproduct. X-ray tube na ngwaọrụ dị na ya maximizes mmepụta nke photons na dissipates okpomọkụ dị ka ngwa ngwa o kwere omume.

The tube bụ a dịtụ mfe ngwaọrụ, a na-gụnyere abụọ bụ isi ndị na - a cathode na ihe anode. Mgbe ugbu a na-aga si cathode na anode, na electrons ida ike, nke na-eduga ọgbọ nke X-ụzarị.

anode

The anode bụ a akụrụngwa, agaghi asu emission nke elu-ike photons emepụta. Nke a bụ a dịtụ oke metal mmewere nke na jikọọ na mma osisi nke eletriki circuit. Ọ nwere isi ihe abụọ ọrụ:

• Ọ atọghata elektrọn ume X-ray radieshon,
• Ọ dissipates okpomọkụ.

The ihe maka anode họrọ aka ọrụ ndị a.

N'eziokwu, ọtụtụ ndị electrons ga-etolite a elu-ike photons, kama okpomọkụ. Ruru nke ngụkọta ike, nke a na-converted n'ime X-radieshon (Cop)-adabere abụọ ihe:

• ọnụọgụ nzùrùòkè (Z) nke anode ihe onwunwe,
• elektrọn ike.

Na ọtụtụ x-ray akpa dị ka a ihe onwunwe nke anode eji tungsten, onye ọnụọgụ nzùrùòkè bụ hà 74. Na mgbakwunye na nnukwu Z, a metal nwere ụfọdụ ndị ọzọ e ji mara nke-eme ka ọ kwesịrị ekwesị n'ihi nzube a. Tungsten bụ ihe pụrụ iche na ya ike na ịnọgide na-enwe ike mgbe kpụ ọkụ n'ọnụ, nwere nnukwu agbaze uche na a ala evaporation ọnụego.

Ruo ọtụtụ afọ, ndị anode ka nke dị ọcha tungsten. Na-adịbeghị anya, anyị malitere iji nke a metal alloy na rhenium, ma naanị n'elu. Self anode n'okpuru tungsten-rhenium mkpuchi mere nke ìhè, ezi okpomọkụ-nchekwa. Abụọ dị otú ahụ bekee molybdenum na graphite.

The X-ray tube eji maka mammography, e mere na anode, ntekwasa na molybdenum. Nke a ihe onwunwe nwere onye n'etiti ọnụọgụ nzùrùòkè (Z = 42), nke site na photons na e ji mara ike, adabara Ndekọ obi. Ụfọdụ mammography ngwaọrụ nwekwara a abụọ anode, kpụrụ si rhodium (Z = 45). Nke a na-eme ka o kwe omume na-amụba ike na nweta ukwuu penetration maka oké ara.

The ojiji nke tungsten-rhenium alloy mma na ogologo oge okpomọkụ mmepụta - na oge arụmọrụ ngwaọrụ na anode mere nke dị ọcha tungsten na-ebelata n'ihi thermal mmebi ka elu.

Ọtụtụ n'ime ndị anode nwere udi nke tapered discs na ofu na moto aro, nke na-agbagharị ha na dịtụ elu gbapụrụ ọsọ n'oge nke emission nke X-ụzarị. Nzube nke adiana - mwepụ nke okpomọkụ.

Baịbụl hiwere isi n'ebe ntụpọ

The X-ray ọgbọ akụkụ bụghị dum anode. Ọ na-adị na a obere ebe nke ya elu - na Baịbụl hiwere isi n'ebe ntụpọ. Akụkụ ikpeazụ kpebisiri size nke elektrọn doo na-abịa site cathode. Na ọtụtụ ndị na ọ nwere a akụkụ anọ udi dịgasị n'ime 0.1-2 mm ngwaọrụ.

The x-ray tube imewe na a ụfọdụ size nke Baịbụl hiwere isi n'ebe ntụpọ. The nta ya bụ, obere ngagharị blur na elu sharpness, na ihe ọzọ bụ na, na mma okpomọkụ dissipation.

Baịbụl hiwere isi n'ebe ntụpọ size bụ a na-akpata na a ga-atụle mgbe ị na-ahọrọ na-X-ray tube. Manufacturers emepụta ngwaọrụ na obere Baịbụl hiwere isi n'ebe ntụpọ, ebe ọ dị mkpa iji nweta elu mkpebi na obere ezu radieshon. Ka ihe atụ, ọ na-achọrọ na-amụ obere na siri akụkụ ahụ dị ka mammography.

The X-ray tube tumadi na-emepụta Baịbụl hiwere isi n'ebe tụrụ na abụọ nha - nnukwu na obere, nke nwere ike họrọ ọrụ dị na oyiyi na-akpụ usoro.

cathode

Isi ọrụ nke cathode - n'ịwa electrons na-achịkọta ha n'ime a doo eduzi ndị anode. Ọ n'ozuzu mejupụtara a obere gburugburu waya (filament) agbakwunyere na a cup ekara ezumike.

Electrons agafe circuit nwere ike anaghị adịkarị-ahapụ onye na-eduzi na-ahapụ a free ohere. Otú ọ dị, ha nwere ike ime ya, ma ọ bụrụ na ha na-ezuru ike. Na a usoro maara dị ka thermal emission, okpomọkụ na-eji na-achụpụ ndị electrons si cathode. Nke a na-ekwe mgbe nsogbu na ihe kpọpụrụ x-ray tube esịmde 10 ^-6 -10 ^-7 Torr. Art. The yarn na-ewe iwe na n'otu ụzọ ahụ dị ka a gburugburu filament oriọna site agafe a ugbu a therethrough. Ọrụ cathode ray tube na-esonyere kpo oku ka okpomọkụ luminescence Ndahie thermal ike na ya na electrons.

balloon

The anode na cathode na-ẹdude ke a kaa akara ụlọ - cylinder. The balloon na ọdịnaya na-emekarị kwuru na dị ka ihe wet, nke nwere a mmachi ndụ na ike ga-anọchi. The x-ray tube n'ozuzu nwere a iko bọlbụ, ọ bụ ezie na metal na seramiiki cylinders eji maka ụfọdụ ngwa.

Isi ọrụ bụ na-akwado na akpa na-akpa iche nke anode na cathode, na ịnọgide na-enwe agụụ. Nrụgide na kpọpụrụ x-ray tube na 15 ° C bụ 1.2 × 10 ^-3 Pa. Ọnụnọ nke gas na tank ga-ekwe ka ọkụ eletrik ndiwet site ngwaọrụ kpam kpam, ọ bụghị naanị na ụdị ihe elektrọn doo ya.

ụlọ

X-ray tube ngwa ndị dị otú ahụ na, na mgbakwunye na nke Herọd na nkwado nke ndị ọzọ mmiri, ọ na-eje ozi dị ka a ọta ahu na-amịkọrọ na ụzarị ọkụ, ma e wezụga n'ihi na ọ bara uru doo agafe window. Ya dịtụ ukwuu mpụga n'elu dissipates ọtụtụ okpomọkụ site na ngwaọrụ. The mbara n'etiti shei na wet jupụtara mmanụ na-enye mkpuchi na obi jụrụ ya.

yinye

Eletriki circuit ejikọ ekwentị a ike isi iyi, nke a na-akpọ a generator. Source na kwadoro site na netwọk na-atọghata ndị nwetụ ugbu a na-eduzi ugbu a. The generator-enye gị ohere ịgbanwe ụfọdụ afọ nke yinye:

• KV - voltaji ma ọ bụ eletriki nwere;
• MA - ugbu a nke na-aga site na tube;
• S - oge ma ọ bụ ikpughe oge, na ụmụ irighiri ihe nke a nke abụọ.

The circuit enye ije nke electrons. Ha na-ebubo na ike, agafe generator, na-enye ya onye anode. Ka ha ije emee abụọ mgbanwe:

• eletriki nwere ike converted n'ime kinetic ike;
• kinetic, n'aka nke ya, na converted n'ime X-ray radieshon na okpomọkụ.

nwere

Mgbe electrons abata na karama, ha nwere ike eletriki ike, nke a kpebisiri ike site ego nke KV voltaji n'etiti anode na cathode. The X-ray tube a ejikwara na a voltaji n'ịwa 1 KV nke ọ bụla urughuru ga nwere 1 keV. Site ukpụhọde KV, ndị ọrụ na-enye onye ọ bụla elektrọn bụ a ụfọdụ ego nke ike.

kinetics

Low mgbali na kpọpụrụ x-ray tube (na 15 ° C na ọ bụ 10 ^-6 -10 ^-7 Torr. V.) Enye ohere ahụ n'okpuru ihe nke emission na thermionic electric ike enwupụta si cathode na anode. Nke a na ike accelerates ha, dapụtara na ụba na-agba na kinetic ume ma nwere nēfedakwasi. Mgbe a urughuru ala na anode, ya nwere na-efu, na ihe nile nke ya ike na converted n'ime kinetic ike. 100-keV elektrọn esịmde a ọsọ ukwuu karịa ọkara ìhè ọsọ. Egbu elu nke urughuru na-selata ngwa ngwa na-atụfu ha kinetic ike. Ọ atụgharịa X-ụzarị ma ọ bụ okpomọkụ.

Electrons abịa na kọntaktị na onye atọm nke anode ihe onwunwe. Radieshon N'ịbụ ha mmekọrịta orbitals (X-ray photons), na na a isi (bremsstrahlung).

nkịtị ike

Onye ọ bụla elektrọn na atọm nwere ụfọdụ na-adịgide adịgide ike, nke na-adabere na size nke ikpeazụ na larịị nke na urughuru na-emi odude. The nkịtị ike na-arụ ọrụ dị mkpa na ọgbọ nke ndị e ji mara X-ụzarị na dị mkpa iji wepu ihe elektrọn si atọm.

bremsstrahlung

Bremsstrahlung arụpụta kasị ukwuu ọtụtụ photons. The electrons banye n'ime n'ime anode ihe onwunwe na inyịme nso ntọala, mehieworonụ na decelerated ndọda ike atọm. Ume ha furu efu n'oge a ná nzukọ-egosi na ụdị nke X-ray photon.

nso nke

Nanị ole na ole photons nwere onye ike nso elektrọn ike. Ihe ka ọtụtụ n'ime ha na ọ bụ ala. Iche na e nwere a ohere ma ọ bụ ubi gburugburu isi, agaghi asu electrons ahụmahụ n'ọrụ "mgbochi." A na ubi nwere ike kere n'ime zones. Nke a na-enye a na-ele nke ubi isi nke lekwasịrị atọm na center. Kọmputa na-ada n'ebe ọ bụla lekwasịrị na-decelerated na site na X-ray photon. Ahụ na-ada nke dịkarịrị nso na center, na-kacha kpughere na Ya mere ida kasị ike, na-amị nnọọ elu-ike photons. Electrons abanye ná mpụta na mpaghara na-enwe a na-adịghị ike na mmekọrịta na n'ịwa photons nke ala ume. Ọ bụ ezie na ebe nwere otu n'obosara, na ha nwere a dị iche iche ebe dabere na anya si ntọala. Ebe ọ bụ na ọnụ ọgụgụ nke ndị ahụ merenụ na mpaghara, na-adabere na ya ngụkọta ebe, ọ bụ doro anya na mpụga ebe weghara ihe electrons na ime ka ndị ọzọ photons. ike X-ray ụdịdị dị iche iche nwere ike buru amụma site nlereanya a.

E _max photons isi bremsstrahlung ụdịdị dị iche iche nke kwekọrọ na E _max electrons. N'okpuru ebe a, na usen photon ike enwekwu ha nọmba.

A ịrịba ama ọtụtụ ndị photons nke ala ume etinye obi gị dum ma ọ bụ ẹdụk, dị ka ha na-agbali gabiga elu nke anode tube ma ọ bụ igbe iyo. Nzacha bụ n'ozuzu dabere na mejupụtara na ọkpụrụkpụ nke ihe onwunwe site na nke okporo osisi na-aga, na nke a na-ekpebi ikpeazụ ụdị nke ala-ike ụdịdị dị iche iche usoro.

mmetụta KV

The elu-ike akụkụ nke ụdịdị dị iche iche na-ekpebi voltaji x-ray akpa na kV (kilovolt). Nke a bụ n'ihi na ọ na-ekpebi na ike nke electrons eru anode, na photons ike nwere ike karịrị nke a. N'okpuru ọ bụla voltaji na-agba ọsọ X-ray tube? The kacha photon ike kwekọrọ na kacha etinyere nwere. Nke a voltaji nwere ike ịdị iche n'oge ikpughe ruru ka nwetụ ugbu a na netwọk. Na nke a, E _max elu voltaji kpebisiri ike site photon oscillation oge KV _p.

Ọzọkwa nwere quanta, KV _p ekpebi ego nke radieshon N'ịbụ a nyere ọnụ ọgụgụ nke electrons eru anode. Ebe ọ bụ na ngụkọta arụmọrụ nke bremsstrahlung radieshon na-amụba site ahụ merenụ elektrọn ike na-abawanye, nke a kpebisiri ike KV _p, a na-egosi na ndị KV _p emetụta arụmọrụ nke ngwaọrụ.

Na-agbanwe agbanwe KV _p, na-emekarị na-agbanwe ihe ụdịdị dị iche iche. Ngụkọta nke ebe n'okpuru ike usoro na-anọchi anya na ọnụ ọgụgụ nke photons. Unfiltered ụdịdị dị iche iche bụ a triangle, na ego nke radieshon ke hà ka ndị square KV. Na ọnụnọ nke iyo na-enwekwu KV abawanye penetration nke photons, nke ebelata pasent nke ẹdụk radieshon. Nke a na-eduga ná ụba radieshon mkpụrụ.

e ji mara radieshon

The ụdị mmekọrịta na site na ndị e ji mara radieshon mejupụtara elu-ọsọ nkukota na orbital electrons. Mmekọrịta nwere ike na-ewere ọnọdụ mgbe a akụkụ E nke _urughuru nwere ukwuu karịa nkịtị ike nke atọm. Mgbe a na ọnọdụ a na-zutere, na e nwere a nkukota, na elektrọn na-kụrụ aka. Nke a doo oghe ọnọdụ, jupụta site na urughuru a elu ume larịị. Ka anyị na-na elektrọn enye ume enwupụta n'ụdị X-ray photon. Ọ na-akpọ ihe e ji mara radieshon, ebe ọ bụ na E bụ photon e ji mara chemical mmewere site na nke anode e mere. Dị ka ihe atụ, mgbe otu elektrọn na-kụrụ aka K tungsten oyi akwa _njikọ na E = 69,5 keV, na ohere jupụtara na ihe elektrọn si L-larịị _{nkwurịta okwu} na E = 10.2 keV. E ji mara X-ray photon nwere ike hà dị iche n'etiti abụọ etoju, ma ọ bụ 59,3 keV.

N'ezie, anode ihe onwunwe na-eduga ná a ọnụ ọgụgụ nke e ji mara X-ray ume. Na nke a emee n'ihi electrons na dị iche iche ike na ọkwa (K, L, wdg) nwere ike kụrụ aka bombarding ahụ na ohere wee jupụta a dịgasị iche iche nke ike na ọkwa. Ezie na ohere L-larịị site photons na ha ume bụ oke obere maka ojiji na-achọpụta ọrịa Onyonyo. Onye ọ bụla e ji mara ike e nyere a designation nke na-egosi orbital, nke a ohere, na ihe index nke na-egosi ihe elektrọn iyi chọrọ. Alfa (α) na-egosi na index nke na-ejuputa elektrọn si L-larịị, na beta (β) na-egosi ndochi larịị nke M ma ọ bụ N.

• Ụdịdị dị iche iche tungsten. The e ji mara radieshon nke metal na-arụpụta a linear ụdịdị dị iche iche esịnede ọtụtụ pụrụ iche ume na braking site na-aga n'ihu na-ekesa. The ọnụ ọgụgụ nke photons kere ọ bụla e ji mara ike, ji na na puru nke ejuputa na ohere K-larịị na-adabere na orbital.
• Ụdịdị dị iche iche molybdenum. Anodes a metal eji maka mammography, na-emepụta abụọ zuru ezu ufiop e ji mara x-ray ume: K-Alfa na 17,9 keV na K-beta na 19,5 keV. The kacha nso nke X-ray akpa, nke na-enye ohere iji nweta ihe kacha mma itule n'etiti iche na irradiation dose maka nkezi ara size enweta ke E _p = 20 keV. Otú ọ dị Bremsstrahlung-emepụta ihe na ike. Na mammography ngwá maka wepụ achọghị akụkụ nke ụdịdị dị iche iche na-eji molybdenum iyo. Nyo na-arụ ọrụ na ụkpụrụ nke «K-onu." Ọ na-amịkọrọ radieshon na ngafe elektrọn nkịtị ike na K-larịị molybdenum atọm.
• The ụdịdị dị iche iche nke rhodium. Rhodium nwere ọnụọgụ nzùrùòkè 45, molybdenum - 42. Ya mere, e ji mara X-ụzarị nke a rhodium anode ga nwere ubé elu ike karịa na nke molybdenum na ndị ọzọ penetrating. Ọ na-eji maka Onyonyo na ok ara.

Anodes na abụọ n'elu ebe, molybdenum, rhodium, nwee ọrụ iji họrọ a nkesa kachasị ara nke dị iche iche size na njupụta.

The utịp ke ụdịdị dị iche iche KV

KV uru nke ukwuu na-emetụta ndị e ji mara radieshon, ie. K. Ọ gaghị-emepụta ma ọ bụrụ na obere KV K-ume larịị electrons. Mgbe KV karịa nke a fọrọ uru, ego nke radieshon bụ n'ozuzu proportional ka ihe dị iche na nbata-uzọ KV tube KV.

The ike ụdịdị dị iche iche nke photons nke X-ray doo enwupụta si ngwaọrụ kpebisiri ike site ọtụtụ ihe. Dị ka a na-achị, ọ mejupụtara bremsstrahlung na ndị e ji mara na mmekọrịta.

The ikwu mejupụtara nke ụdịdị dị iche iche na-adabere na anode ihe onwunwe, KV na iyo. Na a tube na a tungsten anode emission e ji mara na-adịghị kpụrụ na KV <69,5 keV. Na elu ụkpụrụ nke HF eji na-achọpụta ọrịa ọmụmụ, e ji mara radieshon enwekwu ngụkọta radieshon 25%. The molybdenum ngwaọrụ ya nwere ike iru a nnukwu òkè nke ngụkọta-amụba ikike.

arụmọrụ

Naanị a obere akụkụ nke ume nye site electrons converted n'ime radieshon. Isi nta na-etinye obi gị dum na converted n'ime okpomọkụ. radieshon arụmọrụ a kọwara dị ka nta nke ngụkọta nwetara ike site n'ozuzu electric nyere anode. The ihe nke chọpụta arụmọrụ nke X-ray tube na-etinyere voltaji KV na ọnụọgụ nzùrùòkè Z. The ndika ruru nke na-esonụ:

• Arụmọrụ = KV x Z x 10 ^-6.

Na mmekọrịta dị n'etiti arụmọrụ na KV nwere a kpọmkwem mmetụta na ndị bara uru iji X-ray akụrụngwa. N'ihi na okpomọkụ ọgbọ nke tube nwere a ịgba na ọnụ ọgụgụ nke electric ike na ha nwere ike dissipate. Ọ na-eweta na ike nke ngwaọrụ ịgba. Na-amụba KV, Otú ọ dị, ego nke radieshon emepụta site onye nke okpomọkụ budata enwekwu.

The ndabere nke arụmọrụ nke X-ray ọgbọ na mejupụtara nke anode bụ naanị nke agụmakwụkwọ mmasị n'ihi na ọtụtụ ngwaọrụ eji tungsten. Isịneke bụ molybdenum na rhodium, na-eji na mammogram. Arụmọrụ nke ndị a ngwaọrụ bụ budata ala maka tungsten n'ihi na ha na ala ọnụọgụ nzùrùòkè.

irè

Arụmọrụ X-ray tube na a kọwara dị ka ego nke irradiation millirentgenah nye a mgbe na center nke bara uru doo nsannsan 1 m si Baịbụl hiwere isi n'ebe ntụpọ ọ bụla 1 más electrons agafe ngwaọrụ. Ya uru na-anọchi anya ikike nke ngwaọrụ iji tọghata ike nke ebubo ahụ na X-ray radieshon. Ọ-enye gị ohere ikpebi ikpughe onye ọrịa, na snapshot. Ka arụmọrụ, arụmọrụ nke ngwaọrụ na-adabere na ọtụtụ ihe, gụnyere KV, na voltaji ife ụdị, na anode ihe na ogo nke elu mmebi nke nyo ngwaọrụ na oge nke iji.

KV-management

Voltaji KV X-ray tube irè akara mmepụta radieshon. Dị ka a na-achị, ọ na-chere na mmepụta bụ proportional na square nke KV. Ibawanye KV ikpughe enwekwu 4 ugboro.

waveform

The waveform akọwa usoro nke KV dịgasị na n'oge ọgbọ nke radieshon ruru ka cyclic ọdịdị nke ike. Eji ọtụtụ dị iche iche waveforms. The n'ozuzu ụkpụrụ bụ: nta mgbanwe ke udi KV, ndị X-ray radieshon na-emepụta rụọ ọrụ nke ọma. The ngwá ọrụ ọgbara ọhụrụ mee generators na dịtụ mgbe nile KV.

X-ray akpa: Manufacturers

Oxford Instruments Company manufactures iche iche ngwaọrụ, gụnyere iko, ike na 250 W, 4-80 kV nwere, na Baịbụl hiwere isi n'ebe ntụpọ 10 microns na a dịgasị iche iche nke anode ihe, t. H. Ag, Au, Co, ČR, Cu, Fe, knife, PD, RH, edebata, W.

Varian awade n'elu 400 dị iche iche nke ọgwụ na ahụ ike na ulo oru X-ray akpa. Ọzọ mara emepụta bụ Dunlee, ge, Philips, Shimadzu, Siemens, Toshiba, IAE, Hangzhou Wandong, Kailong et al.

Na Russia emepụta X-ray akpa "Svetlana-Roentgen". Ke adianade ọdịnala ngwaọrụ na n'usoro na anyịnya anode ụlọ ọrụ manufactures ngwaọrụ nke oyi cathode luminous agbanwe oge na-achịkwa. Uru ndị na-esonụ ngwaọrụ:

• na-arụ ọrụ a na-aga n'ihu na usu ụdịdị;
• enweghị inertia;
• inye iwu osisi ike nke Ikanam ugbu a;
• ụdịdị dị iche iche na-adị ọcha;
• ekwe omume nke X-ray radieshon ná mgbanwe nke osisi ike.