头瞄用红外管最好买什么样规格的呢？

hbk0401

最近有项目要采购一批元器件，想顺便买一堆回来玩，下面这样规格型号正确不？

名称             规格     LED封装           封装     颜色  发光角   波长         
红外发射管    5mm    无色散射(W)      直插     红外  120      850或920

厂家应该很多吧？

oscarnobel

波长可以再大点的  940nm

hbk0401

为什么波长要大点呢？
是容易透过滤光片，还是摄像头更敏感呢？

oscarnobel

可见光波长390-780nm  红外大于760nm  所以尽量选择远离可见光的波段  然后调整FreeTrack的灵敏度  尽最大可能避免无关光源的干扰  个人见解哈

hbk0401

回复 4# oscarnobel


    嗯，精辟！

yiyp77

我在这买的：

0.3W 5mm 120度 草帽型 940nm 无红爆 红外线发射管

http://item.taobao.com/item.htm?id=3518263945

hbk0401

回复 6# yiyp77


    这个很符合，够给力！已通知深圳供应商去联系了

Akar

更新：
Wii对850nm和940nm红外的实验数据摘录
来源：http://www.wiimoteproject.com/  inio Wiki Admin

To determine the relative sensitivity of the Wii Remote, two leds with similar characteristics were used: SFH4231 (940nm, 180mW TRP @ 1A) and SFH4230 (850nm, 200mW TRP @ 1A).  Both devices provide an approximately Lambertian distribution of light, with a 1A maximum continuous current and 1.8V drop.

The LEDs were attached in series with a laboratory power supply, 5-digit ammeter, and 0.5-ohm resistor.  The LEDs were positioned vertically approximately 30cm apart, facing a Wii Remote approximately 5m away.  Measurements were taken with camera gain values between 0x10 to 0x40 and minimum blob size of 3.  For each configuration, the minimum current at which each LED became visible was recoded.  Gain values higher than 0x40 resulted in the 850nm LED being undetectable even at 1A.



Without filter window in place: The 940nm LED was detectable with approximately 12% the current required to detect the 850nm LED.
With filter window in place: The 940nm LED was detectable with approximately 15% the current required to detect the 850nm LED.
Executive summary:  The Wii Remote is at least 5 times more sensitive to 940nm than 850nm.

结论：

无滤光片的情况下：940nm的LED需850nm12%的电流即可被wiimote探测到；
有滤光片的情况下：940nm的LED需850nm15%的电流即可被wiimote探测到；
对Wiimote来说，940nmLED有着至少5倍于850nmLED的被探测效率；
无论850nm抑或是940nm的LED都可以被wiimote探测到，但是要达到同样的效果，850nm的LED需至少5倍于940nmLED的功率。

hbk0401

果然是波长越长，越容易穿过传输介质！