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Can Widecom re-invent itself?

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SLC vs SLI vs CIS

What exactly is the SLC (Single Line Contact) wide format scanning that Widecom rate so highly? It is not mentioned anywhere except on their website. Today, all the buzz is about CIS (Contact Image Sensor) optical imaging technolgy, the new standard for scanning large format technical drawings.

It wasn't always so. When Widecom was developing its SLC wide format scanning technology in the early 1990s, the technology they were looking to displace in the marketplace was CCD (Charge Coupled Device). CCD had been in use in large format scanners since the very first wide format scanner in 1970.

Widecom CCD Large Format Scanner Presentation
Widecom Explanation of CCD Technology.
Photo credit: The Widecom Group Inc.

Widecom produced a presentation in the 1990s which showed the use of CCD technology "from the 1970s" and the benefit of its new SLC technology as an alternative. Included in this was a product comparison which Widecom was still using in 2007!

In this presentation Widecom's references to the Colortrac 360/380, Contex FSS/FSC 5000/8000 and Vidar TruScan wide format scanners are so hopelessly out-of-date that this product comparison is of no use to anyone but a historian. It clearly shows how Widecom's current (old) products are trapped in time and how desperate its need is for new ones.

To see Widecom's PDF presentation of their SLC technology, (as supplied to us), click here. EDITOR'S NOTE: You will need to Rotate the presentation in your Browser. Readers with Internet Explorer should right click on the image and select Rotate Clockwise.

In the Beginning .... CCD (Charge Coupled Device)

CCD is the oldest optical imaging technology. Being first, it was used by all major wide format scanner manufacturers and quickly became the industry standard.

CIS technology uses folded optics. Light is thrown onto the drawing as it passes through a CCD wide format scanner. The reflected image is bounced off a series of mirrors, passed through lenses and directed at cameras housed inside the scanner. The wider the CCD scanner, the more cameras are needed; the more cameras, the greater the cost and the need for accuracy in stitching the images together.

To provide these sensitive components with the stability to achieve accurate results, CCD scanners were originally housed in heavy metal frames. The overall result in the early 1990s was a very expensive, very heavy wide format scanner which invariably had stitching issues and which was not particularly sharp due to the length of the light path. However, it did have a wide colour gamut suitable for scanning colour artwork and graphics. It wasn't totally suited to scanning monochrome technical drawings but in the absence of an alternative no-one was able to argue otherwise.

The new kid on the block .... SLC (Single Line Contact)

SLC imaging technology (aka direct contact array) was the first attempt to reduce the cost of CCD-based scanners by adopting the direct contact imaging technique used in fax machines. Unlike CCD scanners where folded light travels a long, complicated route to multiple cameras, the big idea behind SLC technology was to shorten the light path by putting the drawing being scanned in direct close contact with a single line of image sensors. At the time this was a heresy which challenged conventional wisdom.

In Widecom's early SLC technology, the scanner included a 36" fiber optic array with 8mm "image sensor chips" aligned to create a 36" length light sensor. Illumination was from a 36" fluorescent lamp, although this was later replaced by LEDs. The fiber optic array acted as a lens and focused the scanned image on the image sensor chips.

Widecom claimed that as their image sensor chips contained pixels larger than those of chips used in other scanners, their contact scanners require less light exposure and, therefore, operate faster than other scanners. ... SLC technology provides superior reliability and error-free scans, for a real environment scanner." (Presumably everyday work in the real world!). "It's fiber optic selfoc lens array provides high accuracy and distortion free scans, compared to image problems created by folded path antiquated lens systems, still used by some of our competitors." (Sic!)

Still bullish today, Widecom's website claims its large format SLC scanners incorporate "industry leading edge Widecom technology sought after by all our competitors. The industry standard for all new scanners, WideCom's single line contact scanning technology has been proven over and over again over the last 5 years. It replaces out-of-date multiple camera type systems developed in the 1970s." Widecom's references to "the last 5 years" refer to events during the gay 1990s, not the 20 naughties!

One serious "competitor keeping a close watch on Widecom's "leading edge" SLC technology was ANA Tech of Littleton, CO, USA, then a division of Intergraph.

When Widecom released its first SLC scanner in 1994, ANA Tech's first "SLI" (Single Line Imaging) scanner, the Eagle 3840 SLI, had not yet been released. ANA Tech (acquired by Colortrac in 1999) would unveil the monochrome ANA Tech Eagle 3840 SLI in 1995. ANA Tech's use of the term "SLI" (Single Line Imaging) as a product description shows its desire to catch up with and get in on Widecom's new wide format scanning technology.

If SLC and SLI technologies were not close, why did ANA Tech choose to use the SLI name to identify its product? Essentially, SLC and SLI are much the same technology with differences in each manufacturer's application. Taken further, Widecom's SLC and ANA Tech's SLI are largely CIS technology by another name. Widecom deserves credit for being first to produce a CIS-type wide format scanner. It was some achievement.

Now everyone is doing it .... CIS (Contact Image Sensor)

Unlike Widecom's single line contact array, modern CIS scanners use five or six short CIS arrays, (much like those in A4 desktop scanners), arranged in a staggered pattern. Other than that these images need to be stitched together, just as in CCD scanners, CIS, SLC and SLI technology is much the same.

Like SLC, CIS large format scanning technology places the document being scanned in close proximity to the sensors capturing the image. This results in a sharper image and a lighter, more affordable scanner. CIS is today's new standard for scanning technical drawings while CCD is still preferred by a majority of graphics professionals because its wider colour gamut is more suitable for high quality colour capture.

While no manufacturer today uses the SLC name, CIS wide format scanners are built by Colortrac, Contex, Graphtec and ROWE, as well as OEM'ed by companies like KIP, Paradigm and others. As a result, Widecom's claim that it developed an industry standard is correct but confusing given its emphasis on calling it SLC rather than CIS.

Widecom were never to capitalise on the success of being first in this new market. While being first gave Widecom bragging rights over CCD manufacturers, sustaining product development would prove much tougher. Despite the relative sophistication of its wide format SLC scanners by 1999 and the lead which it enjoyed, Widecom would fail to excite the market and sell its aggressively priced SLC scanners in high-enough volumes.

Going into the 21st Century, Widecom allowed others to catch up. In 1999 ANA Tech and its patents were acquired by Colortrac. In 2002 Graphtec introduced the CS1000, a "true" CIS wide format scanner, followed by the Colortrac SmartLF 4080 in 2004, the first aggressively priced CIS large format colour scanner. CIS technology would march on to become the technical document scanning standard. It just wouldn't be called SLC.

Widecom started the CIS ball rolling with its SLC technology. Ultimately, even Contex, long resistant to CIS scanners, would realise that it could not deny the rise of CIS technology forever. Incredibly, when Contex belatedly introduced its impressive CIS-based SD Series large format scanner range in 2008, Widecom was still promoting its 1999 vintage scanners on a web site last updated in 2003! How the wheel had turned!

Somehow, with so much going for it, Widecom got left behind. For this reason, we question if Widecom can now reinvent itself as a large format scanner manufacturer. Given what's gone before, do Widecom have the will to pick up the ball and run?

Lets look at what happened to Widecom.

Footnote:
As the leading CCD (charge couple device) wide format scanner manufacturer, Contex vigorously opposed the rise of CIS (contact image sensor) technology. Contex damned CIS technology as suited only to fax machines, saying it was "adapted to rather than designed for wide format scanning". Just how much did Widecom's development of SLC technology colour Contex's perception of early CIS technology and its defence of CCD?

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