Those companies knew they had a captive audience, so they bought up as many journals as they could. Journal articles aren’t interchangeable commodities like corn or soybeans—if your science supplier starts gouging you, you can’t just switch to a new one. Adding to this lock-in effect, publishing in “high-impact” journals became the key to success in science, which meant if you wanted to move up, your university had to pay up. So, even as the internet made it much cheaper to produce a journal, publishers made it much more expensive to subscribe to one.
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通过在间隔像素上叠加一层微观遮罩结构，这些 OLED 像素的发光角度会大幅缩窄至正前方约 45° 的范围内，从而形成一片「窄角发光像素」：