Selection of High Precision Materials / Durability and Inspection
To obtain the most effective X-ray transmission and absorption, as well as grid density uniformity and precise geometric arrangement for strip focusing, our grids utilises the finest precision materials, such as aluminum strips with a purity of 99.99% and a thickness tolerance of ± 0.02mm, and lead strips with a purity of 99.85% and a thickness tolerance of ±.001mm.
Each grid strip is laminated and baked after the gluing procedure. This ensures absolute rigidity between the strips as well as heat and moisture resistance. It also completely prevents warping and cracking over time. Each grid is subjects to radiographic testing prior to shipment and only those grids which have passed the test for perfect strip alignment are delivered to our customers. The test film supplied with all our grids is your assurance of quality.
|Grid Composition Part||Density||Interspacer (Aluminium)||X-Ray Absorbing Material (Lead)|
|40L||0.20 m/m||0.050 m/m|
|60L||0.12 m/m||0.050 m/m|
|70L||0.10 m/m||0.050 m/m|
|80L||0.08 m/m||0.050 m/m|
|Thickness of Line (CM) : Ratio||6:1||8:1||10:1||12:1||15:1|
|40L||1.6 mm||2.0 mm||2.4 mm||2.8 mm||3.2 mm|
|60L||1.02 mm||1.28 mm||1.5 mm||1.74 mm||2.1 mm|
|70L||1.04 mm||1.24 mm||1.44 mm||1.74 mm|
|80L||0.94 mm||1.04 mm||1.20 mm||1.44 mm|
Three Types of X-Ray Grid Strip Positioning
Ratio Available in 5:1 to 15:1 Density
- 60 lines/inch (23 lines/cm)
- 72 lines/inch (28 lines/cm)
- 85 lines/inch (34 lines/cm)
- 103 lines/inch (40 lines/cm)
- 130 lines/inch (51 lines/cm)
- 150 lines/inch (60 lines/cm)
X-Ray Grids Focal Range
Standard focal ranges available: Short(26" -32"), Medium(34" -44), Long(40" -72", 48" -72", or 60" -72) and infinity (parallel). Special focal ranges may be accommodated per your specifications.
|28 - 48, 48 - 72||71 - 122, 122 - 183||5:1||Focused|
|48 - ∞||122 - ∞||5:1||Parallel|
|28 - 48, 48 - 72||71 - 122, 122 - 183||6:1||Focused|
|48 - ∞||122 - ∞||6:1||Parallel|
|26 - 32, 34 - 44, 48 - 72||66 - 81, 86 - 122, 122 - 183||8:1||Focused|
|36 - 40, 60 - 72||91 - 102, 152 - 183||10:1||Focused|
|36 - 40, 60 - 72||91 - 102, 152 - 183||12:1||Focused|
The lower the ratio, the wider the range of usable focal lengths that can be used with the grid. For example, with an 8:1 ratio that has been made with a 38" focal length, it can be used with focal lengths between 34" and 44". When using a higher ratio, such as 12:1, the range would only be 36" to 40".
Parallel X-Ray Grids
Parallel grids are used for operational research and traumatology since exact centering is impossible in these cases. The scattered radiation absorbing strips are vertical and parallel to the grid surface. The strips, generally, run parallel to the long dimension of the grid. In order to get a vivid radiograph, focal distance of parallel grids must be 150 cm - infinity since the scattered radiation absorbing strips are not exactly parallel to the diverging radiation.
General x-ray grid sizes are film sizes (inside grid). Overall dimensions are 2.54 cm (1 inch) larger than film sizes in each direction except the standard BUCKY GRID size 17 1/4" x 18 7/8" and 18 x 18".