TAOSINC which is a division of Texas Instruments has their own line of devices which specialize in light sensing or light to voltage conversion.

TCS230 – 4-Channel Light to Frequency
TSLB257 - Blue light to voltage converter
TSLG257 – Green light to voltage converter
TSLR257 – Red light to voltage converter

A qoute from the TAOSINC RGB LTV sensor page:

“The integrated color LTV sensors combine a photodiode, color filter, and transimpedance amplifier on a single die. The output is then fed to an ADC for digital processing. TAOS’ solution requires fewer components, saves board space and reduces assembly cost over a discrete photodiode approach. TAOS’ solution also simplifies design and board layout because sensitive analog circuitry is integrated on-chip, which also improves the noise immunity. The Color LTV devices are ideal for applications such as colorimetry, printing process control, display color correction, and selectively ambient light detection or rejection. ”

Some electronics companies offer free sample products for evaluation and testing. The free sample products may range from wires, switches, LEDs, logic gates, analog ICs  and microcontrollers. If you know some of these companies, then you may have noticed that most of them are not shipping to Philippines. Why are they not sending free samples to Philippines?. Actually, some of them did send free samples to Philippines but only for a limited time. Most of these companies would ban countries which resell free sample products or abuse the free samples program by ordering too many products in such a short period of time. Fairchild Semiconductors used to send tons of LEDs, seven segment displays and  phototransistors to Philippines. Fairchild semiconductors noticed that there were too many orders coming from Philippines in a very short time and some Juan Dela Cruz is using too many addresses so that he can order more free samples and resell it to his fellow students. To add insult to injury, there are reported cases of electronics store asking for free samples and selling free sample products on their stores as brand new Class-A items. Free samples are not guaranteed to work as the commercial version and do not have guarantees that they would work as specified. If you ever find a company that do send free samples to Philippines, my advice to you is to keep it as a secret or share it only to your friends whom you know that is not abusive and would respect the rules of the free sampling program.

Good luck to all ECEs that are going to take the board exam.