Table 4 Summary results of vertical illumination, contrast ratio and vector/ scalar ratios for task surface illumination of 400 Lux

Ambient 400 Sur 0 Task 0

227

245

1.8:1

1.6:1

1.27

1.52

Ambient 100 Sur 0 Task 300

73

82

5.5:1

4.9:1

0.12

1.28

Ambient 100 Sur 100 Task 200

118

146

3.9:1

2.7:1

1.70

1.58

Ambient 100 Sur 150 Task 150

142

178

2.8:1

2.2:1

2.01

1.70

Ambient 100 Sur 200 Task 100

172

219

2.3:1

1.8:1

2.23

1.79

Ambient 100 Sur 300 Task 0

228

293

1.8:1

1.4:1

2.48

1.91