如题，见
http://www.pixelhk.com/en/proview.asp?P_ID=1543
介绍了一种无线实时取景遥控器，主要原理和功能是
Info.: 　 1.  LV-W1 image transmit is using 2.4GHz frequency channel, 3 specific channels.
2.  Shutter control is using 433MHz frequency channel (available to use another frequency channel). 3 specific channels.
3.  Operating distance range is up to 80M.
4.  The display is protected by coating; it’s not easy to get scratch.
5.  3inch TFT display, adjustable the brightness .
6.  Resolution: 960 X 240
7.  3.7V 1200mAh lithium battery. Working hour: Transmitter --- 8 hours or above. Receiver ---   5hours or above.
8.  The receiver is usable to connect the camera directly, just like CT-122.
     Use VD-936 (optional) to connect and transfer the live view to PC.
9.  Compatible for camera which included AV Output and shutter release socket.
10.Charging method: via charger or USB cable for charging  the battery inside the device.
这个技术不复杂，无非是液晶电视/数码相框+发射机+无线遥控器，国内都有十分成熟的产品，看那个山寨厂家能够借鉴这个设计，做一个类似产品出来。

如果用电脑接收，可以使用USB线的话，无需任何其他设备，利用EOS Utility 软件就可以了。如果是无线的，也有原厂的无线手柄，只是较贵。

我个人认为用电脑做接收比较实用性。

这个有市场，关注

国外的那个好像要接近2000元，山寨版打个对折，加上电视（应该就是现成的）或MP4功能，应该会有销路

这个不难弄吧，电子城里有现成的发射机、解码器、液晶总成，简单组装一下就行了，花不了多少钱。
问题是搞出来谁会买。