Digital radiographic inspection has a very critical technical metric - the resolution of the image.
Resolution is the ability to distinguish the minimum distance between two neighbouring details per unit length. It is affected by a combination of geometric ambiguity (focal spot size and magnification) and intrinsic ambiguity (pixel size of the detector).
The function of the double filament image quality meter is to measure the (unsharpness) of the image resolution and to test the performance of the digital radiographic system! What is a Dual Filament Mass Gauge
A dual filament mass gauge (German) is manufactured according to ISO 19232-5/ASTM E2002 and consists of 13 or 15 wire pairs encapsulated in a rigid transparent plastic material. The diameter of the dual-filament radiometer wires, and the distance between the wires, are equal, and each pair contains two wires of circular cross-section.
It is used to determine the geometric unsharpness Ug of radiographic and real-time radiographic systems, and can also be used to determine the base spatial resolution SRb of X-ray digital imaging detection systems (CR/DR). Principle of Resolution Measurement in Dual Filament Imaging Mass Meter (DFIMM)
In a two-filament image quality meter, the spot size of the light can be limited by adjusting the distance between the filaments. When the diameter of the spot is smaller than the resolution of the system, the interference fringes between the filaments are no longer clearly visible, thus determining the resolution.
Corresponding image resolution requirements (national standard)
In the digital imaging image resolution analysis, usually using "double filament image quality meter" for testing, the national standard requirements are shown in the table below: Introducing the KOWOTEST Dual-Filament Image Quality Meter
The German KOWOTEST double filament image quality meter is a specialised tool for X-ray inspection, digital radiography of welded seams, digital X-rays and other fields. It complies with standards such as EN 13068 (Radiographic Inspection), EN 14784 and ISO 13671 (CR - Computed Radiography with Imaging Plate) and is used for assessing the basic spatial resolution in image opacity (film and digital images) and in digital images.
Classification of KOWOTEST Double Filament Mass Gauges
1、Duplex IQI - 13D: Pairs from 1D to 13D
2、Duplex IQI - 15D: Pairs from 1D to 15D
3、Duplex IQI - 17D: Pairs from 4D to 17D
Parameter description of KOWOTEST double filament image quality meter
⏩ Dual Filament Imager contains 13 pairs of filaments ranging from 1D with a diameter of 0.80 mm to 13D with a diameter of 0.05 mm.
⏩1D to 3D wires are tungsten and the 4D to 13D are made of platinum.
⏩ The spacing of each pair of wires is the same size as the diameter of the wires.
⏩ The filaments are cast in a clear wear-resistant and dimensionally accurate plastic material.
⏩ The standard name and product serial number are also cast in so that they will be displayed on each radiographic image, ensuring consistency of assay standards.
⏩ Dual Filament Imaging Mass Meter has been tested by BAM Berlin.
Use of the KOWOTEST Dual Filament Mass Gauge
1. The double filament image quality meter should be used together with the line or hole image quality meter.
2, should be placed on the source side of the object being examined, and should be as close as possible to the axis of the ray beam, and perpendicular to the axis.
3, with the aid of a 4x magnifying glass to observe the dual-filament image quality meter image, ****** line pairs, the image is exactly two double line spacing can be recognised under the limit of the two independent line transition to a single line of the image, at this time is considered to be the limit of discernible values. To put it simply, that is, when observing the image generated by the dual-filament image quality meter, the more clear double lines can be observed, the better, the finer the better.
4, the image opacity U can be expressed by 2d, where d is the width of the line and the distance between the lines. As a leading high-end manufacturer of X-ray digital imaging equipment in the field of non-destructive testing, SinoCom has always insisted on taking customer needs as the guide, and constantly improving the quality of products and service level. We provide global customers with high-quality and reliable industrial DR, industrial CT and other X-ray flaw detection equipment, as well as industry-leading NDT technical support and services, and escort the high-quality development of equipment manufacturing products with convenient and efficient digital visualisation of China-ray products and technologies.