DpiX expects line of AMLCD monitors to support digital-detector business

Company's Expression 100 delivers high resolution

Flat-panel detector developer dpiX has rolled out a new line of active-matrix liquid crystal displays (AMLCDs) that the company believes will help support its digital x-ray detector business. Manufacturing both detectors and displays will enable the Palo Alto, CA, firm to make better use of its manufacturing capacity, which may result in lower prices relative to its competition for both monitors and detectors, according to dpiX executives.

DpiX in November introduced Expression 100, a line of AMLCD monitors that the company thinks could become a viable alternative to CRT-based monitors for high-end imaging applications. The new monitors also have sharper image quality and a larger viewing area than most other AMLCDs, which are primarily found on laptop computers. Expression 100 is a 19-inch flat-panel color monitor with a resolution of 1280 x 1024, a color-bit depth of 24 bits in 16.7 million colors, and a brightness of 45 footlamberts. The monitors also support full-motion video at 30 fps.

Rather than sell into the laptop market, dpiX will target Expression 100 at high-end imaging applications, such as medical imaging and military avionics. Within medical imaging, the company hopes the displays will prove popular wherever high-resolution color is needed. Color Doppler ultrasound is one such application, as are workstations used for postprocessing, according to Carl Cobb, general manager of display products at the company.

"Our commercial strategy is focused on markets like medical imaging and high-end workstation graphics: all those areas where detail and accuracy and high-quality imaging make a difference to the person using the system," Cobb said.

DpiX's AMLCDs may be more appropriate than CRT-based monitors for some uses due to several key features, Cobb said. Their light weight and small size relative to CRT monitors would make them attractive for use on a portable ultrasound scanner, and the displays' immunity to magnetic distortion means they don't require the shielding needed by CRT displays located near MRI scanners. DpiX is supplying samples of the 19-inch Expression 100s to OEMs at a list price of $10,000 and can negotiate lower prices for volume purchases by OEMs.

Despite Expression 100's high-end specifications and features, the product does not address the gray-scale monitor market, which composes the lion's share of the medical imaging display industry. While dpiX declined to state whether it would develop a gray-scale version of Expression 100, Cobb said that the company is seriously investigating the concept.

Integrating displays with detectors. Expression 100 is based on the same core amorphous silicon thin-film transistor (TFT) technology used in dpiX's FlashScan 20 digital x-ray detectors, and this similarity is at the core of dpiX's business strategy, according to Jean-Pierre Georges, general manager of dpiX's sensor products group. The company addresses two separate markets with output from its flat-panel fabrication facility, a capability that other digital detector developers have not publicly stated they have.

"The synergy we have at dpiX is that we are targeting both high-end niche markets in displays as well as x-ray sensors, which is going to increase our volume and increase our capability and synergy of technology between both devices," Georges said. "DpiX's goal is to manufacture as many arrays as possible for as many customers as possible, because volume is the name of the game as far as making sure the technology is cost-effective."

DpiX may also be able to explore interesting new capabilities for its products due to their similar technological origins. For example, if an x-ray image acquired on a FlashScan 20 detector was displayed on a hypothetical gray-scale version of Expression 100, each pixel on the display would correspond to the same pixel location on the detector. This might help clinicians locate very small structures such as microcalcifications.

DpiX is seeing strong demand for its digital-detector technology as its OEM partners pursue the development of digital x-ray systems, Georges said. And the market appears to be moving beyond the prototype stage: DpiX's partners are using its arrays in commercial-level devices, and many are planning product launches this year.

"We definitely have customers buying in what I would call production volume," Georges said.

DpiX provides its technology to OEMs on three levels. At the most basic level, dpiX provides a glass substrate and TFT array, with the customer supplying all the required electronics. At the next level, the company supplies a flat-panel module with the array, an x-ray-sensitive phosphor layer, and the first level of integration components. FlashScan 20 represents the highest level of technology, consisting of a digital detector that can be integrated into an x-ray system on almost a plug-and-play basis, Georges said.

DpiX is working to improve the electronics of the arrays for better signal-to-noise ratio and better dynamic range, and is also expanding the size of the arrays it offers to customers. FlashScan 20 has a 20 x 25-cm (8 x 10-inch) active area, which limits the product to applications using a small field-of-view. The company has a sensor in development with a 30 x 40-cm (12 x 16-inch) active area, and recognizes that it also needs to develop a 14 x 17-inch array to address most of the radiography market.

"No doubt there is a need to go to 14 x 17, and that's our next development project for 1998," Georges said. "The goal is to have a 14 x 17 subsystem available by the RSNA show next year."