David Carey, Portelligent
TechOnline

On a recent excursion to the camera store to pick a digital SLR for teardown, I got sidetracked. Stacked in a corner of the display case was a cache of cheap cameras, with resolutions that began at Common Intermediate Format (CIF) but extended, in some cases, up to the same multi-megapixel range of their far-pricier neighbors.

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At the bottom was a teeny camera from Vivitar that measured around 6 x 4 cm and even came with a key chain attached. Resolution was 352 x 288 (CIF), and functions included a Webcam and video capture, though storage capacity restricted video clips to just a few seconds. A "bonus" carrying case joined up with a USB cable, AAA battery and photo-editing software. While the product package gave an optimistic retail price of $39.99, a sticker added later proclaimed, "Wow! Only $10!"

Vivitar kept everything cheap. A diminutive, 1/7-inch CMOS image sensor from PixArt of Taiwan was paired with an image processor from the same company, and 8 Mbytes of SDRAM served for working memory. By limiting resolution, the sensor could be made quite small, minimizing the processor horsepower needed for basic image correction and compression. The claimed 2 Mbytes of user memory was not a standalone chip; a portion of the SDRAM was for image storage. This money-saving trick required that users download the images before removing the battery.

(Click on image to enlarge)

Underscoring the design's penny-pinching nature was the chip-and-wire assembly of the image processor, whose bare silicon gets wire-bonded directly to the board and then "glob topped." A small, inexpensive monochrome segment LCD provided the user interface. A rough manufacturing-cost estimate of $6 to $7 (inclusive of all accessories) pointed to slim, but still positive, profits--even at the "Wow! Only $10!" price.

Not too far up the ladder was a $49 Disney-branded camera that added a flash lamp, LCD and nonvolatile (NV) storage. Resolution was bumped to VGA (640 x 480) with a larger, 1/4-inch Omnivision CMOS sensor and 16 Mbytes of Hynix NAND for permanent image retention. A 1.1-inch color STN LCD, supplied by China's Shenzhen Tongxingda, for image review added about $3 to the parts bill. A glob-topped chip of indeterminate manufacture, joined to 2 Mbytes of Hynix SDRAM for working memory, provided image processing. A small flash from EON held system code. The addition of a Xenon flash, NV memory, more-complex supporting passive component set and fancier casings pushed the production cost toward $20.