Next-generation camera lens assemblies with CMOS image sensors for C-arm X-ray systems can improve image quality while reducing patient dose. Adimec’s RUBY delivers full digital real-time 1k2 30fps imaging for Image Intensifier-based medical X-Ray systems. This is the second installment of a three-part series on Adimec’s new Ruby camera lens assembly (CLA) for X-Ray imaging.

Ruby is designed to reduce costs in fluoroscopy C-arm systems compared to existing CCD-based solutions, while enhancing image quality and lowering patient dose. It operates within a system that is simple to install and service.

Five key parameters define the quality of an X-ray image in mobile C-arm systems: Resolution, Contrast, Dynamics, Noise, and Artifacts. This blog will focus on these aspects relative to the RUBY CLA.

Resolution, measured by pixels per unit area, determines overall image sharpness when optimized for focus and dose. The RUBY provides industry-standard 1k2 or 1 Megapixel resolution. Full automated precision alignment of the sensor to optics ensures optimal Modulation Transfer Function (MTF) at factory level, guaranteeing maximum sharpness across every produced RUBY unit.

Contrast, the ability to discern details in both bright and dark portions, is a strength of CMOS imagers. Ruby’s CMOS technology outperforms CCDs in low-light contrast sensitivity, potentially improving fluoroscopy images or reducing patient dose—depending on system settings. The widely used KAI1020CCD sensor has a dynamic range (DNR) of 60 dB or 1000 gray levels; Ruby’s CMOS sensor exceeds 74 dB or 4000 gray levels. More gray levels translate to greater detail capture, especially in darker image areas (5-20% saturation), which contains crucial clinical information. While actual patient dose depends on radiologist choices, Ruby’s low-light capabilities combined with effective processing may enable lower X-ray exposures.

Dynamics, or blurring from motion, is mitigated by the CMOS global shutter sensor. Ruby supports pulsed and continuous fluoroscopy acquisition like existing global shutter CCD cameras.

Regarding Noise, it’s vital that detector contributions aren’t noticeable to end users. The KAI1020CCD has a read noise of 40 electrons; Ruby’s CMOS sensor reads at just 3.6, offering superior contrast sensitivity. At low light levels typical for X-ray imaging (5-20% saturation), the CMOS-based RUBY captures more detail than traditional CCDs.

Finally, Artifacts are defective pixels that interfere with image quality. Adimec uses proprietary algorithms to correct single isolated defects without affecting clusters—ensuring clinical details aren’t obscured. Defect correction can be disabled if needed; additionally, RUBY applies gain stages effectively for brightness adjustments without introducing artifacts common in uncooled CCD technology.

In summary, the five parameters of X-ray image quality are covered and often exceed comparable CCD-based systems.

Overall, Ruby CLA excels across all five quality metrics compared to typical CCD solutions. Adimec will discuss these advancements at RSNA2017—contact us for details via [email protected] or by subscribing to our blog updates.

Last Updated: 2025-09-04 18:44:22