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Sua loi QR code va that bai quet: tai sao QR cua ban khong quet duoc

Lan ra soat cuoi 2026-05-05. Ban tao mot QR voi Bo Tao QR Code cua chung toi, in tren tap roi hoac dan vao slide, va camera khong bat duoc. Nguyen nhan gan nhu luon la mot trong bon dieu - kich thuoc payload, muc sua loi, do tuong phan, hoac ty le in - va cach sua la co hoc, khong phai phep mau. Huong dan nay goi ten moi cai trong nhu the nao va lam sao de QR quet ngay lan dau.

Cau tra loi 30 giay. Mot QR khong quet duoc khi (1) payload qua dai cho muc sua loi da chon (mau tro nen rat day), (2) tuong phan giua modules va nen qua thap (camera that bai trong moi truong toi hoac khong-trang), (3) ty le in duoi ~2 cm x 2 cm o khoang cach quet, hoac (4) mot phan cua mau dinh vi (ba o vuong goc) bi cat, xuoc, hoac che. Bo Tao QR Code cua chung toi xuat mot PNG; bon kiem tra duoi day cho biet cai nao la van de cu the cua ban va cach khoi phuc.

Nguyen nhan 1: payload qua dai cho bo ma hoa

Mot QR code luu payload trong mot so co dinh "modules" - cac o vuong nho den va trang. Payload cang dai, ban can cang nhieu modules, mau cang day, va o mot diem camera khong the giai quyet modules sach tu khoang cach quet thong thuong cua dien thoai (15-30 cm).

Ba dai payload kich thuoc dang biet:

  • URL ngan hoac van ban duoi ~25 ky tu (vd. https://trangcuaban.com, "WIFI:..." SSID ngan). Mau van thua va quet sach o bat ky kich thuoc hop ly.
  • URL hoac van ban trung binh 25-100 ky tu (vd. URL voi tracking, vCard ngan). Mau bat dau dac len; thuong on nhung canh giac voi tuong phan thap hoac in nho.
  • URL dai hoac vCard day du 100-300+ ky tu (the lien he day du voi dien thoai, email, to chuc, dia chi; URL voi nhieu params tracking). Mau bay gio rat day - kich thuoc in nho se that bai quet.

Sua: rut ngan payload truoc khi tao. Voi URL, bo cac params tracking hoac dung dich vu rut link. Voi vCard, giu chi cac truong thiet yeu (ten, mot dien thoai, mot email). Voi Wi-Fi, khong nhung mot passphrase dai neu ban co the tranh. Re-tao tu Bo Tao QR Code sau khi cat va mau nen long ra ro rang.

Nguyen nhan 2: khong khop muc sua loi

QR code co bon muc sua loi - L (~7% co the khoi phuc), M (~15%), Q (~25%), H (~30%). Muc cao hon nghia la code co the bi che mot phan (chong logo, vet van tay, goc rach) va van giai ma duoc, nhung voi chi phi nhieu modules hon moi ky tu payload.

Danh doi bang ngon ngu don gian:

  • L (Low) - mac dinh cho hau het bo tao bao gom chung toi. Quet nhanh nhat, mau nho nhat o kich thuoc payload nhat dinh. Dung khi QR se duoc hien tren man hinh ky thuat so sach hoac in nguyen so.
  • M (Medium). Mot buffer do tin cay nho voi chi phi mau nho. Dung cho tap roi in ma co the gap hoac vay.
  • Q (Quartile). Khoang 25% cua code co the bi che va quet van hoat dong. Dung khi ban dinh chong mot logo nho o trung tam.
  • H (High). Khoang 30% co the che. Dung cho bien hieu ngoai troi co the phai mau, troc, hoac bi che mot phan.

Bo Tao QR Code tren trang nay xuat o muc L, la mac dinh dung cho su dung ky thuat so va in nguyen so. Neu ban dac biet can dung sai chong, tao QR, boc trong cong cu thiet ke cua ban, va kiem tra quet tu phuong tien cuoi cung thuc su (in o kich thuoc thuc su, gan o khoang cach thuc su) truoc khi di in.

Nguyen nhan 3: tuong phan thap giua modules va nen

Camera dien thoai doc modules nhu nhi phan: toi hoac sang. Neu modules la xam toi tren nen xam sang - hoac te hon, tren nen mau chong cheo voi gia tri module - camera khong the threshold sach va quet that bai. Day la nguyen nhan don pho bien nhat cua "QR ngay do, tai sao dien thoai cua toi khong doc?"

Quy tac tuong phan:

  • Toi tren sang, khong phai sang tren toi. Mac du QR dao nguoc (modules trang tren nen toi) ve mat ky thuat hop le, nhieu camera cu va mot so app tu choi giai ma chung. Giu o toi-tren-sang tru khi ban kiem soat thiet bi quet.
  • Nen ran, khong phai chup anh. Dat QR tren mot anh chup gan nhu khong bao gio hoat dong - tieng on trong anh thoat vao mau module.
  • Den that, khong phai mau toi. Modules xanh toi, do toi, hoac nau toi se quet, nhung chung giam le tuong phan. Neu ban in o kich thuoc nho, uu tien den thuan.
  • Nen trang hoac gan trang. Kem, off-white, vang rat nhat thuong on. Pastel bao hoa rui ro.

Bo Tao QR Code cua chung toi xuat mot PNG den-that-tren-trang-that. Neu ban re-style trong cong cu thiet ke, giu ty le tuong phan cao va re-test voi hai dien thoai khac truoc khi in.

Nguyen nhan 4: ty le in duoi san phan giai camera

Mot QR code can khoang 10 modules moi centimet khoang cach quet tai camera. Mot QR payload ngan co ~21 modules moi canh; mot QR payload dai co ~57+. In o 2 cm x 2 cm va mot URL 25 ky tu on; in cung payload o 1 cm x 1 cm va modules sup do thanh khong doc duoc tren camera dien thoai.

Cac san thuc te ty le in:

  • Danh thiep / sticker / tap roi (khoang cach quet ~15 cm): toi thieu 2 cm x 2 cm cho payload ngan, 3 cm x 3 cm cho trung binh, 4-5 cm x 4-5 cm cho vCard day du.
  • Poster / bien hieu (khoang cach quet 30-60 cm): toi thieu 5 cm x 5 cm; cho bien hieu ngoai troi quet tu ben kia phong, 10-15 cm x 10-15 cm.
  • Slide deck (khoang cach quet thay doi; gia su sau phong ~5 m): it nhat 10 cm x 10 cm render, va pre-test tu hang ghe sau thuc su truoc bai noi.

PNG tu Bo Tao QR Code la mot anh raster; neu ban upscale ma khong artifact anti-aliasing, no van quet duoc. Neu ban can in rat lon va PNG trong cuc o ty le, regenerate o kich thuoc xuat lon hon hoac chuyen sang SVG qua bo chuyen doi SVG sang PNG dao nguoc (hau het cong cu QR cung xuat SVG; cua chung toi xuat PNG ma scale sach voi nearest-neighbour resampling).

Cat va mau dinh vi: that bai pho bien thu nam

Moi QR co ba "mau dinh vi" o vuong lon o ba goc (tren trai, tren phai, duoi trai). Camera dinh vi QR bang cach phat hien chung. Neu bat ky cai nao trong chung bi cat, che, hoac xuoc, quet that bai hoan toan - khong phai "voi loi", ma hoan toan, vi camera khong the tim code dau tien.

Khi bo tri mot QR tren mot the hoac tap roi, de it nhat mot vien trang rong 4 modules ("vung yen tinh") xung quanh toan bo code. Khong de luoi bo cuc hoac hinh dang nen cham vao cac o vuong dinh vi. Neu QR cua ban that bai tren trang in ma quet tot tren man hinh, day la cai dau tien kiem tra - nhat ban in va kiem tra ba o vuong goc so voi phien ban man hinh.

Luong chan doan nhanh

  1. QR co quet tu man hinh khong? Neu khong, bo ma hoa khong phai van de - payload hoac tuong phan moi la.
  2. Neu co tu man hinh nhung khong tu in: do code in. Moi canh < 2 cm? In lon hon.
  3. Van that bai tu in o > 2 cm: kiem tra cac mau dinh vi goc bang mat. Ca ba o vuong hien dien va khong cat?
  4. Van that bai: kiem tra tuong phan. Toi tren sang? Den that tren nen trang? Khong co mau tinh chong QR?
  5. Van that bai tren payload dai: regenerate voi URL ngan hon hoac vCard cat. Mau payload dai qua day cho nhieu camera dien thoai.

Cai gi KHONG gay that bai quet (huyen thoai pho bien)

  • "Ban can mot bo tao QR tra phi." Khong. Dac ta QR mo; mot bo tao mien phi trong trinh duyet nhu cua chung toi tao ra mot code quet giong het mot bo tra phi. Ban tra cho analytics hoac branding, khong phai kha nang quet.
  • "QR cong hoac xoay khong quet." Camera dien thoai hien dai xu ly xoay vua phai va cong nhe be mat tot. Wrap nang (xung quanh mot chai) pha quet, nhung mot nhan phang tren mot be mat hoi cong thuong on.
  • "Dien thoai cu khong the quet QR." Quet QR ban dia xuat hien o iOS 11 (2017) va o camera stock Android cung thoi gian. Bat cu thu gi trong 7 nam qua co tich hop san.
  • "Ban can cai app QR." Khong tren iPhone hoac Android hien dai. Neu mot tap roi yeu cau nguoi doc cai "app quet QR", QR duoc dung trong marketing 2008 va nen duoc thay the.

Cong cu va huong dan lien quan tren trang nay

  • Bo Tao QR Code - bo tao trong trinh duyet da tao ra PNG ban dang debug.
  • Compress Image - neu tep PNG in lon va ban can gui mot tap roi nho hon qua email, nen PNG cua QR truoc.
  • SVG to PNG - cho nha thiet ke regenerate mot QR vector o mot kich thuoc raster cu the.
  • Photo Editor - de them mot vien trang vung-yen-tinh hoac dat QR tren mot tile nen sach truoc khi in.

← Quay lai Bo Tao QR Code

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