Patent ID: 8234858

Claim:
A particulate matter concentration measuring apparatus configured to measure a particulate matter concentration in exhaust gas flowing in an exhaust line of a diesel engine, the apparatus comprising: an exhaust gas extraction line that is branched from the exhaust line and has a flow passage cross-sectional area smaller than a flow passage cross-sectional area of the exhaust line; a particulate matter detection filter that is provided in the exhaust gas extraction line and configured to catch particulate matter; a heating unit configured to heat the caught particulate matter; and a differential pressure detection unit configured to detect a differential pressure generated between an inlet and an outlet of the particulate matter detection filter, wherein the heating unit is configured to apply 50% or more of a calorific value for heating the particulate matter to an area making up 30% of the particulate matter detection filter on an upstream side of an exhaust gas flow.